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Dynamics of oscillator populations with disorder in the coupling phase shifts New J. Phys. (IF 3.3) Pub Date : 2024-02-28 Arkady Pikovsky, Franco Bagnoli
We study populations of oscillators, all-to-all coupled by means of quenched disordered phase shifts. While there is no traditional synchronization transition with a nonvanishing Kuramoto order parameter, the system demonstrates a specific order as the coupling strength increases. This order is characterized by partial phase locking, which is put into evidence by the introduced novel correlation order
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Polarization state conversion achieved by chiral mechanical metamaterial New J. Phys. (IF 3.3) Pub Date : 2024-02-27 Hicham Mangach, Younes Achaoui, Muamer Kadic, Abdenbi Bouzid, Sébastien Guenneau, Shuwen Zeng
Recently, metamaterials have driven advancements in wave propagation and polarization control. Chiral elastic metamaterials, in particular, have attracted considerable attention due to their distinctive properties, such as acoustical activity and auxeticity. Such characteristics arise from the additional degrees of freedom for tuning the embedded micro- and macro-rotations. In this study, we demonstrate
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Hamiltonian switching control of noisy bipartite qubit systems New J. Phys. (IF 3.3) Pub Date : 2024-02-26 Zhibo Yang, Robert L Kosut, K Birgitta Whaley
We develop a Hamiltonian switching ansatz for bipartite control that is inspired by the quantum approximate optimization algorithm, to mitigate environmental noise on qubits. We demonstrate the control for a central spin coupled to bath spins via isotropic Heisenberg interactions, and then make physical applications to the protection of quantum gates performed on superconducting transmon qubits coupling
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Quantum speed limits for change of basis New J. Phys. (IF 3.3) Pub Date : 2024-02-26 Moein Naseri, Chiara Macchiavello, Dagmar Bruß, Paweł Horodecki, Alexander Streltsov
Quantum speed limits provide ultimate bounds on the time required to transform one quantum state into another. Here, we introduce a novel notion of quantum speed limits for collections of quantum states, investigating the time for converting a basis of states into an unbiased one as well as basis permutation. Establishing an unbiased basis, we provide tight bounds for the systems of dimension smaller
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Hybridization of electromagnetic multipoles in a nanoscatterer in the presence of another nanoscatterer New J. Phys. (IF 3.3) Pub Date : 2024-02-23 Sagar Sehrawat, Radoslaw Kolkowski, Andriy Shevchenko
Coupling between multipolar modes of different orders has not been investigated in depth, despite its fundamental and practical relevance in the context of optical metamaterials and metasurfaces. Here, we use an electromagnetic multipole expansion of both the scattered fields and the oscillating electric currents to reveal the multipolar excitations in a nanoparticle positioned close to another nanoparticle
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Powering an autonomous clock with quantum electromechanics New J. Phys. (IF 3.3) Pub Date : 2024-02-23 Oisín Culhane, Michael J Kewming, Alessandro Silva, John Goold, Mark T Mitchison
We theoretically analyse an autonomous clock comprising a nanoelectromechanical system, which undergoes self-oscillations driven by electron tunnelling. The periodic mechanical motion behaves as the clockwork, similar to the swinging of a pendulum, while induced oscillations in the electrical current can be used to read out the ticks. We simulate the dynamics of the system in the quasi-adiabatic limit
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Microscopic contributions to the entropy production at all times: from nonequilibrium steady states to global thermalization New J. Phys. (IF 3.3) Pub Date : 2024-02-23 Ayaka Usui, Krzysztof Ptaszyński, Massimiliano Esposito, Philipp Strasberg
Based on exact integration of the Schrödinger equation, we numerically study microscopic contributions to the entropy production for the single electron transistor, a paradigmatic model describing a single Fermi level tunnel coupled to two baths of free fermions. To this end, we decompose the entropy production into a sum of information theoretic terms and study them across all relevant time scales
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Generalization of Gisin’s theorem to quantum fields New J. Phys. (IF 3.3) Pub Date : 2024-02-23 Konrad Schlichtholz, Marcin Markiewicz
We generalize Gisin’s theorem on the relation between the entanglement of pure states and Bell non-classicality to the case of mode entanglement of separated groups of modes of quantum fields extending the theorem to cover also states with undefined particle number. We show that any pure state of the field which contains entanglement between two groups of separated modes violates some Clauser–Horne
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Operational significance of nonclassicality in nonequilibrium Gaussian quantum thermometry New J. Phys. (IF 3.3) Pub Date : 2024-02-23 Safoura Mirkhalaf, Mohammad Mehboudi, Zohre Nafari Qaleh, Saleh Rahimi-Keshari
We provide new operational significance of nonclassicality in nonequilibrium temperature estimation of bosonic baths with Gaussian probe states and Gaussian dynamics. We find a bound on the thermometry performance using classical probe states. Then we show that by using nonclassical probe states, single-mode and two-mode squeezed vacuum states, one can profoundly improve the classical limit. Interestingly
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Sensory adaptation in a continuum model of bacterial chemotaxis—working range, cost-accuracy relation, and coupled systems New J. Phys. (IF 3.3) Pub Date : 2024-02-23 Vansh Kharbanda, Benedikt Sabass
Sensory adaptation enables organisms to adjust their perception in a changing environment. A paradigm is bacterial chemotaxis, where the output activity of chemoreceptors is adapted to different baseline concentrations via receptor methylation. The range of internal receptor states limits the stimulus magnitude to which these systems can adapt. Here, we employ a highly idealized, Langevin-equation
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Current driven properties and the associated magnetic domain walls manipulation in U-shaped magnetic nanowires New J. Phys. (IF 3.3) Pub Date : 2024-02-22 Guangjian Gong, Yu Wang, Zhongchen Gao, Jingguo Hu
Based on the extended Landau–Lifshitz–Gilbert method, the properties of current driven domain wall movement in U-shaped magnetic nanowires and the effect of spin wave assistance on their properties have been investigated. The results show that changes of the curvature radius of magnetic nanowire can cause the additional pinning action and the pinning action will weaken the speed of current driven domain
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One-dimensional extended Su–Schrieffer–Heeger models as descendants of a two-dimensional topological model New J. Phys. (IF 3.3) Pub Date : 2024-02-22 Tao Du, Yue-Xun Li, He-Lin Lu, Hui Zhang
The topological phase diagrams and finite-size energy spectra of one-dimensional extended Su–Schrieffer–Heeger (SSH) models with long-range hoppings on the trimer lattice are investigated in detail. Due to the long-range hoppings, the band structure of the original SSH model becomes more complicated and new phases with the large Zak phase can emerge. Furthermore, a seeming violation of bulk-edge correspondence
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Light-induced nonlinear spin Hall current in single-layer WTe2 New J. Phys. (IF 3.3) Pub Date : 2024-02-22 Pankaj Bhalla, Habib Rostami
In this theoretical investigation, we analyze light-induced nonlinear spin Hall currents in a gated single-layer 1T ′ -WTe2, flowing transversely to the incident laser polarization direction. Our study encompasses the exploration of the second and third-order rectified spin Hall currents using an effective low-energy Hamiltonian and employing the Kubo’s formalism. We extend our analysis to a wide frequency
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Time scales in the dynamics of political opinions and the voter model New J. Phys. (IF 3.3) Pub Date : 2024-02-21 Philipp G Meyer, Ralf Metzler
Opinions in human societies are measured by political polls on time scales of months to years. Such opinion polls do not resolve the effects of individual interactions but constitute a stochastic process. Voter models with zealots (individuals who do not change their opinions) can describe the mean-field dynamics in systems where no consensus is reached. We show that for large populations, the voter
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Continuously monitored quantum systems beyond Lindblad dynamics New J. Phys. (IF 3.3) Pub Date : 2024-02-21 Guglielmo Lami, Alessandro Santini, Mario Collura
The dynamics of a quantum system, undergoing unitary evolution and continuous monitoring, can be described in term of quantum trajectories. Although the averaged state fully characterizes expectation values, the entire ensemble of stochastic trajectories goes beyond simple linear observables, keeping a more attentive description of the entire dynamics. Here we go beyond the Lindblad dynamics and study
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Irradiation-induced enhancement of Fe and Al magnetic polarizations in Fe60Al40 films New J. Phys. (IF 3.3) Pub Date : 2024-02-20 A Smekhova, Th Szyjka, E La Torre, K Ollefs, B Eggert, B Cöster, F Wilhelm, R Bali, J Lindner, A Rogalev, D Többens, E Weschke, C Luo, K Chen, F Radu, C Schmitz-Antoniak, H Wende
The rise of Fe magnetic moment, changes in Al electronic structure and a variation of Al magnetic polarization in thin films of transition metal aluminide Fe60Al40 have been probed through the order-disorder phase transition by soft x-ray absorption spectroscopy and x-ray resonant magnetic reflectivity in the extreme ultraviolet regime. In a course of the transition induced by 20 keV Ne+ irradiation
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Analysis of satellite-to-ground quantum key distribution with adaptive optics New J. Phys. (IF 3.3) Pub Date : 2024-02-20 V Marulanda Acosta, D Dequal, M Schiavon, A Montmerle-Bonnefois, C B Lim, J-M Conan, E Diamanti
Future quantum communication infrastructures will rely on both terrestrial and space-based links integrating high-performance optical systems engineered for this purpose. In space-based downlinks in particular, the loss budget and the variations in the signal propagation due to atmospheric turbulence effects impose a careful optimization of the coupling of light in single-mode fibers required for interfacing
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Witnessing edge modes in trimerized circuit quantum electrodynamic lattice New J. Phys. (IF 3.3) Pub Date : 2024-02-20 Xuedong Zhao, Yan Xing, Ji Cao, Wen-Xue Cui, Shutian Liu, Hong-Fu Wang
We propose a scheme to investigate and witness edge modes of general one-dimensional photonic trimers in a circuit quantum electrodynamic lattice. These in-gap edge modes are strictly and analytically solved and the criteria for their emergence are indicated respectively. Moreover, the energy spectrum of the system shows two different regimes characterized by a discrepancy in the number of edge modes
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On the conclusive detection of Majorana zero modes: conductance spectroscopy, disconnected entanglement entropy and the fermion parity noise New J. Phys. (IF 3.3) Pub Date : 2024-02-20 Arnav Arora, Abhishek Kejriwal, Bhaskaran Muralidharan
Semiconducting nanowires with strong Rashba spin–orbit coupling in the proximity with a superconductor and under a strong Zeeman field can potentially manifest Majorana zero modes (MZMs) at their edges and are a topical candidate for topological superconductivity. However, protocols for their detection based on the local and the non-local conductance spectroscopy have been subject to intense scrutiny
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The suppression of finite size effect within a few lattice sites New J. Phys. (IF 3.3) Pub Date : 2024-02-19 Tao Liu, Kai Bai, Yicheng Zhang, Duanduan Wan, Yun Lai, C T Chan, Meng Xiao
Boundary modes localized on the boundaries of a finite-size lattice experience a finite size effect (FSE) that could result in unwanted couplings, crosstalks and formation of gaps even in topological boundary modes. It is commonly believed that the FSE decays exponentially with the size of the system and thus requires many lattice sites before eventually becoming negligibly small. Here we consider
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Multipartite entanglement serves as a faithful detector for quantum phase transitions New J. Phys. (IF 3.3) Pub Date : 2024-02-16 Yan-Chao Li, Yuan-Hang Zhou, Yuan Zhang, Yan-Kui Bai, Hai-Qing Lin
We investigate quantum phase transitions (QPTs) in various spin chain systems using the multipartite entanglement measure τSEF based on the monogamy inequality of squared entanglement of formation (EOF). Our results demonstrate that τSEF is more effective and reliable than bipartite entanglement or bipartite correlation measures such as EOF, von Neumann entropy, and quantum discord in characterizing
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Activation of metrologically useful genuine multipartite entanglement New J. Phys. (IF 3.3) Pub Date : 2024-02-16 Róbert Trényi, Árpád Lukács, Paweł Horodecki, Ryszard Horodecki, Tamás Vértesi, Géza Tóth
We consider quantum metrology with several copies of bipartite and multipartite quantum states. We characterize the metrological usefulness by determining how much the state outperforms separable states. We identify a large class of entangled states that become maximally useful for metrology in the limit of large number of copies, even if the state is weakly entangled and not even more useful than
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Quantum-state engineering in cavity magnomechanics formed by two-dimensional magnetic materials New J. Phys. (IF 3.3) Pub Date : 2024-02-16 Chun-Jie Yang, QingJun Tong, Jun-Hong An
Cavity magnomechanics has become an ideal platform to explore macroscopic quantum effects. Bringing together magnons, phonons, and photons in a system, it opens many opportunities for quantum technologies. It was conventionally realized by an yttrium iron garnet, which exhibits a parametric magnon–phonon coupling mˆ†mˆ(bˆ†+bˆ) , with mˆ and bˆ being the magnon and phonon modes. Inspired by the recent
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Interaction graph engineering in trapped-ion quantum simulators with global drives New J. Phys. (IF 3.3) Pub Date : 2024-02-16 Antonis Kyprianidis, A J Rasmusson, Philip Richerme
Trapped-ion quantum simulators have demonstrated a long history of studying the physics of interacting spin-lattice systems using globally addressed entangling operations. Yet despite the multitude of studies so far, most have been limited to studying variants of the same spin interaction model, namely an Ising model with power-law decay in the couplings. Here, we demonstrate that much broader classes
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Tunable chiral spin–spin interactions in a spin-mechanical hybrid system: application to causal-effect simulation New J. Phys. (IF 3.3) Pub Date : 2024-02-15 Bo Li, Xiaoxiao Li, Xixiang Zhao, Yanpeng Zhang, Hongxing Wang, Feng Li
Long-range chiral interactions are very attractive due to their potential applications in quantum simulation and quantum information processing. Here we propose and analyze a novel spin-mechanical hybrid quantum device for designing and engineering chiral spin–spin interactions by integrating spin qubits into a programmable mechanical chain. After mapping the Hamiltonian of the mechanical lattice to
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Influence of gravitational tilt on the thermocapillary convection in a non-axisymmetric liquid bridge New J. Phys. (IF 3.3) Pub Date : 2024-02-15 Shuo Yang, Yupeng Zhang, Jie Cui, Daocheng Qin, Yuhang Wang, Pushi Ge, Jintao Luo, Duojiao Guan, Yunyi Zheng
Fluid slosh caused by residual acceleration in microgravity is a common problem encountered in space engineering. To solve this problem, the ground-based experiment research on the influence of gravity jitter and gravitational tilt on the thermocapillary convection (TCC) transition behaviour of non-axisymmetric liquid bridge has become an important issue in microgravity fluid management. Based on a
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Superconducting state generated dynamically from distant pair source and drain New J. Phys. (IF 3.3) Pub Date : 2024-02-15 E S Ma, Z Song
It has been well established that the origin of p-wave superconductivity is the balance between pair creation and annihilation, described by the spin-less fermionic Kitaev chain model. In this work, we study the dynamics of a composite system where the pair source and drain are spatially separated by a long distance. We show that this non-Hermitian system possesses a high-order exceptional point (EP)
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Systematic design of a robust half-W1 photonic crystal waveguide for interfacing slow light and trapped cold atoms New J. Phys. (IF 3.3) Pub Date : 2024-02-14 Adrien Bouscal, Malik Kemiche, Sukanya Mahapatra, Nikos Fayard, Jérémy Berroir, Tridib Ray, Jean-Jacques Greffet, Fabrice Raineri, Ariel Levenson, Kamel Bencheikh, Christophe Sauvan, Alban Urvoy, Julien Laurat
Novel platforms interfacing trapped cold atoms and guided light in nanoscale waveguides are a promising route to achieve a regime of strong coupling between light and atoms in single pass, with applications to quantum non-linear optics and quantum simulation. A strong challenge for the experimental development of this emerging waveguide-QED field of research is to combine facilitated optical access
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An adaptive Bayesian approach to gradient-free global optimization New J. Phys. (IF 3.3) Pub Date : 2024-02-14 Jianneng Yu, Alexandre V Morozov
Many problems in science and technology require finding global minima or maxima of complicated objective functions. The importance of global optimization has inspired the development of numerous heuristic algorithms based on analogies with physical, chemical or biological systems. Here we present a novel algorithm, SmartRunner, which employs a Bayesian probabilistic model informed by the history of
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Advanced momentum sampling and Maslov phases for a precise semiclassical model of strong-field ionization New J. Phys. (IF 3.3) Pub Date : 2024-02-14 Mads Brøndum Carlsen, Emil Hansen, Lars Bojer Madsen, Andrew Stephen Maxwell
Recollision processes are fundamental to strong-field physics and attoscience, thus models connecting recolliding trajectories to quantum amplitudes are a crucial part in furthering understanding of these processes. We report developments in the semiclassical path-integral-based Coulomb quantum-orbit strong-field approximation model for strong-field ionization by including an additional phase known
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Measuring the nuclear magnetic quadrupole moment of optically trapped ytterbium atoms in the metastable state New J. Phys. (IF 3.3) Pub Date : 2024-02-13 Ayaki Sunaga, Yuiki Takahashi, Amar Vutha, Yoshiro Takahashi
We propose a scheme to measure a nuclear magnetic quadrupole moment (MQM), a CP -violating electromagnetic moment that appears in the nuclear sector, using the long-lived 3P2 metastable state in neutral 173Yb atoms. Laser-cooling and trapping techniques enable us to prepare ultracold 173Yb atoms in the 3P2 state trapped in an optical lattice or an optical tweezer array, providing an ideal experimental
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Optimization of tensor network codes with reinforcement learning New J. Phys. (IF 3.3) Pub Date : 2024-02-13 Caroline Mauron, Terry Farrelly, Thomas M Stace
Tensor network codes enable structured construction and manipulation of stabilizer codes out of small seed codes. Here, we apply reinforcement learning (RL) to tensor network code geometries and demonstrate how optimal stabilizer codes can be found. Using the projective simulation framework, our RL agent consistently finds the best possible codes given an environment and set of allowed actions, including
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Towards the generation of mechanical Kerr-cats: awakening the perturbative quantum Moyal corrections to classical motion New J. Phys. (IF 3.3) Pub Date : 2024-02-12 Rodrigo G Cortiñas
The quantum to classical transition is determined by the interplay of a trio of parameters: dissipation, nonlinearity, and macroscopicity. Why is nonlinearity needed to see quantum effects? And, is not an ordinary pendulum quite nonlinear already? In this manuscript, we discuss the parameter regime where the dynamics of a massive oscillator should be quantum mechanical in the presence of dissipation
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Noise-resilient phase transitions and limit-cycles in coupled Kerr oscillators New J. Phys. (IF 3.3) Pub Date : 2024-02-12 H Alaeian, M Soriente, K Najafi, S F Yelin
In recent years, there has been considerable focus on exploring driven-dissipative quantum systems, as they exhibit distinctive dissipation-stabilized phases. Among them dissipative time crystal is a unique phase emerging as a shift from disorder or stationary states to periodic behaviors. However, understanding the resilience of these non-equilibrium phases against quantum fluctuations remains unclear
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Conservative and nonconservative forces for Mie particles in acoustic trapping New J. Phys. (IF 3.3) Pub Date : 2024-02-09 Huimin Cheng, Xixi Zhang, Xiao Li, Jack Ng
A general acoustic force field can be decomposed into a conservative gradient force (GF) and a non-conservative scattering force (SF), which have very different physical and mathematical properties. However, the profiles of such forces for Mie particles are unknown, let alone their underlying physics. Here, by using a fast Fourier transform approach, we calculated the GF and SF for spherical particle
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Modelling Rabi oscillations for widefield radiofrequency imaging in nitrogen-vacancy centers in diamond New J. Phys. (IF 3.3) Pub Date : 2024-02-09 Simone Magaletti, Ludovic Mayer, Jean-François Roch, Thierry Debuisschert
In this paper we study the dynamics of an ensemble of nitrogen-vacancy centers in diamond when its photoluminescence is detected by means of a widefield imaging system. We develop a seven-level model and use it to simulate the widefield detection of nitrogen-vacancy centers Rabi oscillations. The simulation results are compared with experimental measurements showing a good agreement. In particular
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Quantum imaging beyond the standard-quantum limit and phase distillation New J. Phys. (IF 3.3) Pub Date : 2024-02-09 Simon Schaffrath, Daniel Derr, Markus Gräfe, Enno Giese
Quantum sensing using non-linear interferometers (NLIs) offers the possibility of bicolour imaging, using light that never interacted with the object of interest, and provides a way to achieve phase supersensitivity, i.e. a Heisenberg-type scaling of the phase uncertainty. Such a scaling behaviour is extremely susceptible to noise and only arises at specific phases that define the optimal working point
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Collective motion of pulsating active particles in confined structures New J. Phys. (IF 3.3) Pub Date : 2024-02-09 Wan-hua Liu, Wei-jing Zhu, Bao-quan Ai
The collective motion of pulsating active particles with periodic size contraction is investigated in a two-dimensional asymmetric channel. Our findings reveal that changes in particle size can act as a non-equilibrium driving force, disrupting the system’s thermodynamic equilibrium and leading to the transformation of self-contraction motion into directional motion in the asymmetric channel. The specific
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Real-space decomposition of p-wave Kitaev chain New J. Phys. (IF 3.3) Pub Date : 2024-02-09 D K He, E S Ma, Z Song
We propose an extended Bogoliubov transformation in real space for spinless fermions, based on which a class of Kitaev chains of length 2N with zero chemical potential can be mapped to two independent Kitaev chains of length N. It provides an alternative way to investigate a complicated system from the result of relatively simple systems. We demonstrate the implications of this decomposition by a
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Alternate attractor chimeralike states on rings of chaotic Lorenz-type oscillators New J. Phys. (IF 3.3) Pub Date : 2024-02-09 Hao Zhang, Zhili Chen, Fei Liu, Zhao Lei, Zhigang Zheng, Yu Qian
An interesting alternate attractor chimeralike state can self-organize to emerge on rings of chaotic Lorenz-type oscillators. The local dynamics of any two neighboring oscillators can spontaneously change from the chaotic butterfly-like attractors to the two symmetric and converse ones, which forms alternate attractors on the ring. This is distinctly different from the traditional chimera states with
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Andreev reflection in Euler materials New J. Phys. (IF 3.3) Pub Date : 2024-02-09 Arthur S Morris, Adrien Bouhon, Robert-Jan Slager
Many previous studies of Andreev reflection have demonstrated that unusual effects can occur in media which have a nontrivial bulk topology. Following this line of investigation, we study Andreev reflection by analysing a simple model of a bulk node with a generic winding number n > 0, where the even cases directly relate to topological Euler materials. We find that the magnitudes of the resultant
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Generation and propagation of acoustic solitons in a periodic waveguide of air-water metamaterials New J. Phys. (IF 3.3) Pub Date : 2024-02-08 R Braik, A Elmadani, M Idrissi, Y Achaoui, H Jakjoud
In this study, we propose an equivalent circuit of a metamaterial 1D waveguide. The latter is made of a diphasic medium to induce both non-linearity and dispersion. The balance between these two effects makes it possible to obtain soliton waves not studied in the fluid-fluid metamaterial so far. The purpose of the present paper is to confront the numerical Runge Kutta-based solution to the Transmission
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Topological semimetal phase in non-Hermitian Su–Schrieffer–Heeger model New J. Phys. (IF 3.3) Pub Date : 2024-02-07 Jia-Jie Li, Jing-Quan Li, Yu Yan, Ji Cao, Wen-Xue Cui, Shou Zhang, Hong-Fu Wang
We explore the non-Hermitian Su–Schrieffer–Heeger model with long-range hopping and off-diagonal disorders. In the non-Hermitian clean limit, we find that the phase diagram holds topological semimetal phase with exceptional points except the normal insulator phase and the topological insulator phase. Interestingly, it is found that the topological semimetal phase is induced by long-range nonreciprocal
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Quantum homogenization in non-Markovian collisional model New J. Phys. (IF 3.3) Pub Date : 2024-02-07 Tanmay Saha, Arpan Das, Sibasish Ghosh
Collisional models are a category of microscopic framework designed to study open quantum systems. The framework involves a system sequentially interacting with a bath comprised of identically prepared units. In this regard, quantum homogenization is a process where the system state approaches the identically prepared state of bath unit in the asymptotic limit. Here, we study the homogenization process
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Discontinuous to continuous transition changeover and magnetic helicity reversal in helimagnet nanodisks under torsion New J. Phys. (IF 3.3) Pub Date : 2024-02-07 Xuejin Wan, Anruo Zhong, Yangfan Hu, Xiaoming Lan, Biao Wang
A magnetic skyrmion is topologically protected because it possesses a non-zero topological charge. As a result, the creation or annihilation of a magnetic skyrmion is thought to be initiated by a sudden reversal of local magnetization, and thus cannot occur continuously. Here, we show that this viewpoint is only partially correct by studying the creation and annihilation of an isolated skyrmion in
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Emergent clustering due to quorum sensing interactions in active matter New J. Phys. (IF 3.3) Pub Date : 2024-02-07 Samudrajit Thapa, Bat-El Pinchasik, Yair Shokef
Many organisms in nature use local interactions to generate global cooperative phenomena. To unravel how the behavior of individuals generates effective interactions within a group, we introduce a simple model, wherein each agent senses the presence of others nearby and changes its physical motion accordingly. This generates non-physical, or virtual interactions between agents. We study the radial
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Exploring the quantum vacuum via ultraintense laser-induced refraction of light New J. Phys. (IF 3.3) Pub Date : 2024-02-07 J Wang, G Y Chen, B F Lei, S Jin, L Y Yang, L F Gan, C T Zhou, S P Zhu, X T He, B Qiao
The rapid progress of ultraintense laser technology provides a novel route to explore the quantum vacuum effect in the laboratory. Here, we propose using oblique collisions between an ultraintense pump laser and an x-ray probe laser to experimentally identify the quantum vacuum effect, where the change of the refraction properties including the refraction angle of the probe laser is taken as a detectable
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The electronic and electromagnetic Dirac equations New J. Phys. (IF 3.3) Pub Date : 2024-02-07 Mingjie Li, S A R Horsley
Maxwell’s equations and the Dirac equation are the first-order differential relativistic wave equation for electromagnetic waves and electronic waves respectively. Hence, there is a notable similarity between these two wave equations, which has been widely researched since the Dirac equation was proposed. In this paper, we show that the Maxwell equations can be written in an exact form of the Dirac
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Macroscopic effects in generation of attosecond XUV pulses via high-order frequency mixing in gases and plasma New J. Phys. (IF 3.3) Pub Date : 2024-02-06 V A Birulia, M A Khokhlova, V V Strelkov
We theoretically study the generation of attosecond XUV pulses via high-order frequency mixing (HFM) of two intense generating fields, and compare this process with the more common high-order harmonic generation (HHG) process. We calculate the macroscopic XUV signal by numerically integrating the 1D propagation equation coupled with the 3D time-dependent Schrödinger equation. We analytically find the
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Breaking reflection symmetry: evolving long dynamical cycles in Boolean systems New J. Phys. (IF 3.3) Pub Date : 2024-02-06 Mathieu Ouellet, Jason Z Kim, Harmange Guillaume, Sydney M Shaffer, Lee C Bassett, Dani S Bassett
In interacting dynamical systems, specific local interaction rules for system components give rise to diverse and complex global dynamics. Long dynamical cycles are a key feature of many natural interacting systems, especially in biology. Examples of dynamical cycles range from circadian rhythms regulating sleep to cell cycles regulating reproductive behavior. Despite the crucial role of cycles in
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Bright and dark solitons in a photonic nonlinear quantum walk: lessons from the continuum New J. Phys. (IF 3.3) Pub Date : 2024-02-05 Andreu Anglés-Castillo, Armando Pérez, Eugenio Roldán
We propose a nonlinear quantum walk model inspired in a photonic implementation in which the polarization state of the light field plays the role of the coin-qubit. In particular, we take profit of the nonlinear polarization rotation occurring in optical media with Kerr nonlinearity, which allows to implement a nonlinear coin operator, one that depends on the state of the coin-qubit. We consider the
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Spin-textured Volkov–Pankratov states and their tunnel magnetoresistance response New J. Phys. (IF 3.3) Pub Date : 2024-02-02 Vivekananda Adak, Subhadeep Chakraborty, Krishanu Roychowdhury, Sourin Das
Volkov–Pankratov (VP) states are a family of sub-gap states that appear at the smooth interface/domain wall between topologically distinct gaped states. We carry out quantum transport simulations on one- and two-dimensional lattice models to demonstrate the emergence of such states in the edge spectrum of a quantum spin Hall system subjected to a smoothly varying exchange field that switches its sign
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High key rate continuous-variable quantum key distribution using telecom optical components New J. Phys. (IF 3.3) Pub Date : 2024-02-02 Tao Wang, Peng Huang, Lang Li, Yingming Zhou, Guihua Zeng
Quantum key distribution (QKD) is one quantum technology that can provide secure encryption keys for data transmission. The secret key rate (SKR) is a core performance indicator in QKD, which directly determines the transmission rate of enciphered data. Here, for the first time, we demonstrate a high-key-rate Gaussian-modulated continuous-variable QKD (CV-QKD) using telecom optical components. The
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Structured quantum collision models: generating coherence with thermal resources New J. Phys. (IF 3.3) Pub Date : 2024-02-02 Stefano Cusumano, Gabriele De Chiara
Quantum collision models normally consist of a system interacting with a set of ancillary units representing the environment. While these ancillary systems are usually assumed to be either two level systems or harmonic oscillators, in this work we move further and represent each ancillary system as a structured system, i.e. a system made out of two or more subsystems. We show how this scenario modifies
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NV centres by vacancies trapping in irradiated diamond: experiments and modelling New J. Phys. (IF 3.3) Pub Date : 2024-01-31 S Santonocito, A Denisenko, R Stöhr, W Knolle, M Schreck, M Markham, J Isoya, J Wrachtrup
Advances in applications of nitrogen-vacancy (NV) spin centres in diamond for sensing and quantum metrology depend critically on the NV fabrication methods. One such technique combines epitaxial diamond growth and electron or ion irradiation (He, C, etc), where NVs are activated by vacancy trapping at the nitrogen donor atoms upon thermal diffusion. In this work we study the efficiency of such method
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A quantum fluctuation description of charge qubits New J. Phys. (IF 3.3) Pub Date : 2024-01-31 F Benatti, F Carollo, R Floreanini, H Narnhofer, F Valiera
We consider a specific instance of a superconducting circuit, the so-called charge-qubit, consisting of a capacitor and a Josephson junction that we describe by means of the BCS microscopic model in terms of two tunnelling superconducting systems in the strong-coupling quasi-spin formulation. Then, by means of collective observables we derive the Hamiltonian governing the quantum behaviour of the circuit
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Dynamics of spin relaxation in nonequilibrium magnetic nanojunctions New J. Phys. (IF 3.3) Pub Date : 2024-01-31 Rudolf Smorka, Michael Thoss, Martin Žonda
We investigate nonequilibrium phenomena in magnetic nano-junctions using a numerical approach that combines classical spin dynamics with the hierarchical equations of motion technique for quantum dynamics of conduction electrons. Our focus lies on the spin dynamics, where we observe non-monotonic behavior in the spin relaxation rates as a function of the coupling strength between the localized spin
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Q-deformed rainbows: a universal simulator of free entanglement spectra New J. Phys. (IF 3.3) Pub Date : 2024-01-31 Lucy Byles, Germán Sierra, Jiannis K Pachos
The behavior of correlations across a bipartition is an indispensable tool in diagnosing quantum phases of matter. Here we present a spin chain with position-dependent XX couplings and magnetic fields, that can reproduce arbitrary structure of free fermion correlations across a bipartition. In particular, by choosing appropriately the strength of the magnetic fields we can obtain any single particle
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Measuring relational information between quantum states, and applications New J. Phys. (IF 3.3) Pub Date : 2024-01-30 Michał Oszmaniec, Daniel J Brod, Ernesto F Galvão
The geometrical arrangement of a set of quantum states can be completely characterized using relational information only. This information is encoded in the pairwise state overlaps, as well as in Bargmann invariants of higher degree written as traces of products of density matrices. We describe how to measure Bargmann invariants using suitable generalizations of the SWAP test. This allows for a complete
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One to many one-way control in quadripartite asymmetric Einstein-Podolsky-Rosen steering New J. Phys. (IF 3.3) Pub Date : 2024-01-29 C Xiao, X Y Cheng, J W Lv, Y R Shen, Y X Jiang, L Cheng, Y B Yu, G R Jin, A X Chen
Einstein–Podolsky–Rosen (EPR) steering is different from quantum entanglement because of its unique asymmetry. Multipartite asymmetric EPR steering can break through one-to-one monogamy steering and achieve one to many one-way steering. That is to say, the state of one part can steer the other rest parts simultaneously, while the other parts cannot steer this part. Here, a scheme is proposed to generate