We study the luminescence decay times of Ce3+: Lu2SiO5 scintillator, co-doped with Sc3+ and Li+ ions, under the direct photoexcitation of Ce3+ ions at 337 nm and excitation by a pulsed electron beam with energies of 100 – 300 keV. The cathodoluminescence (CL) and photoluminescence (PL) decay times of studied sample are equal within the experimental error. Two emission bands are found: in the range

We demonstrate a single-longitudinal-mode Ho:GdVO4 continuous-wave (CW) laser at 2048.6 nm. We achieved excellent single-longitudinal-mode performance using a unidirectional ring cavity with an isolator and a half-wave plate. We obtain the maximum output power equal to 965 mW corresponding to a slope efficiency of 12.7%.

Subgrade sea and sky monitoring equipment requires the accurate detection of threat targets in a given area. Due to the extremely complex sea–land–sky backgrounds, the sea–sky line is often submerged in the background. Therefore, we propose an algorithm for accurately detecting sea–sky lines under a complex sea–land–sky background. Based on the analysis of infrared images with sea–land–sky backgrounds

Irradiation of a thermonuclear capsule by a laser-induced X-ray pulse (indirect drive) is a way to maximally reduce the inhomogeneity of the capsule heating and, thereby, to minimize the negative influence of hydrodynamic instabilities on its compression. Nevertheless, the application of this method in the world’s largest NIF facility with a laser pulse energy of about 1.8 MJ at the Lawrence Livermore

In this paper, we present a detailed analysis of the dynamics of the cavity radiation of a coherentlypumped correlated-emission laser. We find that the phase fluctuations and dephasing significantly affect the two-mode squeezing, entanglement, and the radiation intensity. The results obtained show that almost perfectly entangled light can be generated while the rate of dephasing and phase fluctuations

We propose a quasi-D-shaped photonic-crystal-fiber surface-plasmon-resonance (PCF-SPR) biosensor based on ultrashort side polishing. The gold film layer of the ultrashort side-polishing PCF-SPR biosensor is close to the fiber core. It can enhance the surface-plasmon-resonance effect and can test the strong interaction between the samples and the difficulties of the process of lateral fiber transfer

We study the laser-driven generation of thermonuclear neutrons from targets with a microstructured surface in the form of deuterated microwires, using three-dimensional numerical simulation with previously obtained results of large-scale structural optimization of the target, which provides its best heating by femtosecond laser pulses of moderate intensity. We show that, for modern laser technologies

We demonstrate a resonantly-pumped electro-optically Q-switched Ho:GdVO4 laser with an LGS crystal. In the continuous-wave mode, with an absorbed pump power of 15 W, the Ho:GdVO4 laser delivers a maximum output power of 6.2 W and a slope efficiency of 60.0%. With a pulse repetition frequency of 10 kHz, the electro-optically Q-switched Ho:GdVO4 laser produces a maximum average output power of 4.7 W

We demonstrate an efficient diode-pumped Tm:Lu2O3 ceramic laser with resonant pumping scheme. A laser diode at 1.7 μm is employed as the pump source. With an absorbed pump power of 8.2 W, the diode-pumped Tm:Lu2O3 ceramic laser produces an output power of 3.3 W at 2.06 μm corresponding to a slope efficiency of 64.9% with respect to the absorbed pump power. Furthermore, the M2 factor of Tm:Lu2O3 ceramic

We introduce a new kind of quantum states generated by repeated actions of the creation and annihilation operators on the standard nonlinear coherent states. We discuss the Klauder minimum set of conditions, which is necessary to obtain the coherent states. As an application, we consider the new quantum states to generate high amounts of entanglement, employing a beam splitter device. To detect the

In this article, we study the strengthening effects of nanosecond laser shock processing (LSP) of a TC17 blade by simulations and experiments. A LSP model of the laser light impact on the TC17 blade is established based on ANSYS/LS-DYNA. We investigate residual stresses with different laser pulse durations along the direction of the blade surface and depth and discuss the influence of different overlap

In free-space optical communication (FSOC), it is necessary to couple optical fibers for application in optical-fiber technology and devices. However, propagation through atmospheric turbulence degrades the single-mode-fiber coupling efficiency (CE). This degradation can be compensated by an adaptive optics (AO) system. In this paper, we analyze the influence of spatial and temporal characteristics

A modified constitutive model, combining laser shock processing and dynamic strain aging (DSA), is used to obtain the compressive residual stress field of In 718 in warm laser shock processing (WLSP) by ABAQUS VUMAT subroutine. In this work, a constitutive model with DSA is simplified by a single equation to integrate the interactions of face-centered cubic (FCC) and body-centered cubic (BCC) crystal

The existence of “barren plateau landscapes” for generic discrete-variable quantum neural networks, which obstructs efficient gradient-based optimization of cost functions defined by global measurements, would be surprising in the case of generic linear optical modules in quantum optical neural networks due to the tunability of the intensity of continuous variable states and the relevant unitary group

We calculate transition amplitudes and probabilities between the coherent and Fock states of a quantum harmonic oscillator with a moving center for an arbitrary law of motion. These quantities are determined by the Fourier transform of the moving center acceleration. In the case of a constant acceleration, the probabilities oscillate with the oscillator frequency, so that no excitation occurs after

A 2 μm laser has important applications and prospects in various fields such as LIDAR, material processing, environmental monitoring, and space communication, as well as fundamental researches. Being designed for the room-temperature operation, our Tm:YLF laser with L flat concave resonator incorporates a laser-diode end-pump setup, in which a volume Bragg grating and double Fabry–Pérot etalons serve

We propose and experimentally demonstrate a novel switchable quadruple-wavelength CW erbium-doped fiber laser, using a linear cavity structure. It is composed of two Sagnac loops that act as cavity mirrors in the resonant cavity. The left loop consists of a 3 dB fiber coupler (FC), a squeezed polarization controller (PC), and a chirped fiber grating. The right loop consists of a 10 dB FC, the same

We present a new numerical algorithm for the simulation of dispersive media. This model named ADETLM is based on the transmission line modeling method with the symmetrical condensed node (SCNTLM) and novel voltage sources and exploits the polarization current density J along with the voltage electric as well as the average approximation. We extend the proposed algorithm to media with dispersions described

We demonstrate a diode-pumped Nd:LaMgAl11O19 laser operating at 1.38 μm band and measure for continuous-wave (CW) laser operation the power from the output couplers (OCs) of different transmittance T. With an absorbed pump power of 6.2 W, we obtain a maximum output power of 570 mW for the OC with T = 4%. For Q-switched operation with this OC, we investigate and analyze laser performance characteristics

With the wide application of laser technology in laser processing and photoelectric detection, the measurement and display of the laser beam polarization has become an extremely important prerequisite. In this paper, we realize the laser polarization measurement tool based on the virtual instrument LabVIEW software platform. The set-up is designated to measure the Stokes parameters for an arbitrarily

We study the dynamics of an electro-optical transducer in the presence of a driving field and a probe field. The nano-electro-optomechanical system (NEOMS) consists of a cavity with a fixed mirror, which is coupled to a vibrating end mirror through an optomechanical coupling, whereas the Coulomb interaction couples the moving mirror with the other moving mirror. In the probe transmission field, four-wave

The efficiency and accuracy of point set registration is always a challenge to deal with. In this paper, we propose an improved algorithm using a scale invariant feature extracted. The larger transformation scale and rotation angle cause lower registration accuracy. The initial corresponding point set can be obtained using a scale invariant feature transform (SIFT) operator. In addition, the geometric

The Langevin equation is used to investigate the state of mode coupling in step-index plastic optical fibers under varied temperature. The numerical integration of the Langevin equation is based on the computer-simulated Langevin force. The solution matches the experimental data reported previously. We find that elevated temperatures of plastic optical fibers are strengthening mode coupling. We show

Under the background that the Earth’s aerosphere contains Kolmogorov and non-Kolmogorov turbulence, it is significant to research the combined influence of these two kinds of atmospherical turbulence on laser-satellite communication. In this paper, based on the power spectra of refractive-index fluctuations for non-Kolmogorov turbulence in the free troposphere and stratosphere, using the extended Rytov

In this paper, we propose a measurement system based on single autocorrelation technology and combined with LabVIEW software platform to realize the real-time online measurement of the femtosecond-laser pulse width. The system uses an experimental device based on the Mach–Zehnder interferometer, where the second-harmonic signal of femtosecond laser is obtained by the nonlinear effect of light and nonlinear

We consider a three-level laser coupled to a two-mode thermal reservoir via a single port mirror. Applying the master equation, we study the effect of decoherence on the squeezing, entanglement, and statistical properties of a two-mode cavity light at a steady state. It turns out that the two-mode thermal reservoir substantially degrades the degree of squeezing and entanglement. However, it significantly

We study the Gaussian pulse propagation and its absorption, dispersion, and distortion in an atomic medium for advanced optical technology. The output pulse intensity distribution in time and Rabi oscillations, as well as the phase of control fields, show significant dark and bright forms of soliton shapes. We investigate the localized intensity of dark and bright solitons with the intensity of control

We describe an extended algorithm for the analysis of the interferograms of complex-structured phase objects, capable of processing the fringes with negative curvature. The algorithm implements nonlinear locally-adaptive processing of interference images, which is based on the analysis of the distribution, variance, and increment of intensity in different directions at each point of the image. The

We study the influence of altitude and speed on aero-optic imaging quality degradation of new laser communication system “Multi-Aperture Transmission and Diversity Reception” of surface-to-air missile. The 3D modeling and meshing of surface-to-air missile are obtained by ANSYS software. The density field distribution around the optical system was analyzed by FLUENT and the nonuniform refractive-index

In this paper, we conduct a simulation research on the filtering effects of various far-field spatial filters (including pinhole filter and various slit filters) and point out that there are obvious filtering differences among them under some conditions, which are always considered to be basically the same, and explain their formation mechanism. The result has certain significance for the slit filters

We introduce a quantum scheme where a single five-level atom interacts with a single-mode cavity field by a time-dependent coupling. During the interaction, the temporal behavior of the quantum entropy in the atomic basis is compared with that of the Mandel parameter used to quantify the nonclassical properties of the field. With the field prepared in a squeezed coherent state, the atomic quantum entropy

We report on efficient passively Q-switched operation of an Yb:YAl3(BO3)4 laser with a 2D MoS2 acting as a saturable absorber, which is the first demonstration of passive Q-switching induced by 2D saturable absorbers in the Yb-ion crystal laser. An average output power of 1.52 W at 1039.6 nm is produced at a pulse repetition rate of 585 kHz, with optical-to-optical and slope efficiencies being 29.3%

We present an easy and at the same time effective computational algorithm for tracing the interferograms of phase objects. The approach to preprocessing of interference patterns, which includes image denoising and removal of distortions, is given. We provide a detailed description of the parabola method involved in the algorithm for searching candidates for extreme points and consider the criteria

In section Acknowledgments, the Russian Science Foundation Grant No. 1871-10091 should read No. 1971-10091.

In section Acknowledgments, the Russian Science Foundation Grant No. 1871-10091 should read No. 1971-10091.

In section Acknowledgments, the Russian Science Foundation Grant No. 1871-10091 should read No. 1971-10091.

We study the possibilities of increasing the light-emission intensity of quantum wells. We describe the influence of the quantum-well width and the effective mass of charge carriers on the radiation intensity. Since the formation of negatively charged layers near the quantum well can increase the photon emission, we propose to form the charged layers with the use of ion implantation. The results of

We present an all-polarization-maintaining (PM) compact passively mode-locked fiber laser using a PM wavelength division multiplexer (WDM)-isolator-tap (WIT) hybrid device with good stability. Compared with inserting the WDM, isolator, and tap into a traditional cavity, only a PM WIT device could simultaneously inject the pump light into the cavity, control the unidirectional operation of the ring

The existence of the spherical aberration of the thermal lens in the crystal has a certain regulatory effect on the distribution of laser modes. In this paper, using the impact of this aberration on the superposition area of TEM01 and TEM10 modes, we carry out an experimental study of a 1064 nm hollow beam and its nonlinear frequency conversion providing a 532 nm hollow beam. Using a plano-concave

We analytically study the problem of pore detection and certification in bulk objects by means of radiography. For an absorbent sample, the optimum thickness for pore imaging and detection is expressed in terms of the linear attenuation coefficient of the material. This can be used to maximize the signal-to-noise ratio by tuning the photon energy of the incident monochromatic beam. The problem is more

We report the mode locking regime of dye laser pumped by 400 ns laser diode pulses. Three green laser diodes operating at 513 nm are used as the pump source. We obtain subnanosecond pulse trains using periodic 1 ns pulse modulation of the power-supply current through the pump diodes. The addition of a saturable absorber results in both a decrease in the pulse duration to 0.2 ns and a good reproducibility

We experimentally register stimulated low-frequency Raman scattering (SLFRS) in the suspension of brome mosaic virus (BMV) in phosphate buffer with very high conversion efficiency. We identify two components of the SLFRS spectrum as the breathing and quadrupole modes of BMV and determine damping characteristics and gain factors for these modes. We show that, using the core–shell model for BMV and taking

We study the propagation dynamics of zeroth-order Bessel–Gauss laser beams in plasma in the relativistic ponderomotive regime of interaction. Based on the paraxial and Wentzel-Kramers-Brillouin approximations, we derive the nonlinear evolution equation governing the laser beam width parameter, in view of the parabolic equation approach. We predict the range of intensity for self-focusing of Bessel–Gauss

We describe a novel chaotic macropulse green laser designed employing the pulse modulation of a 520 nm laser diode with optical feedback. We analyze the characteristics of these chaotic macropulses, in view of effects of the feedback intensity, injection current, modulation voltage, duty cycle, and modulation frequency on the pulses, including their full width at half maximum (FWHM) values and peak

We report the stimulated Raman scattering of light in synthetic diamond microparticles of close sizes (250–300 μm) with the generation of three Stokes satellites under the excitation by ultrashort (60 ps) YAG:Nd3+ laser pulses at a wavelength of 532 nm. The studies performed open up the possibility of creating a laser frequency array with a frequency shift of 1332 cm–1 based on stimulated Raman scattering

Applying the combination of the master and stochastic differential equations, we investigate in detail a continuous-variable entanglement of the twin beam generated by the coherent beat laser containing a parametric amplifier and coupled to thermal light of an external environment. The dipole-forbidden transition of the three-level atoms are coupled by the initial coherent superposition and classical

We study the earliest steps in the radiolysis of a water pentamer in an intense, 800 nm, linearlypolarized fs laser field [I = (0.1 − 50) ∙ 1014 W/cm2] through a real-space, real-time implementation of time-dependent density functional theory nonadiabatically coupled to molecular dynamics. The ionization is enhanced with increasing laser intensity, resulting in the continuous emergence of higher charge

We use Letokhov’s concept of stochastic feedback to interpret experiments on X-ray spontaneous emission from a polydisperse plasma of a nanosecond vacuum discharge (NVD) with a virtual cathode. We develop a diffusion model of stochastic propagation of spontaneous X-ray radiation in the volume of randomly located reflecting clusters. The model provides qualitative explanation of both the experimentally

We propose a temperature sensor based on the graphene-oxide-coated micro-nano-fiber Mach–Zehnder (MZ) interference structure. In the design of the sensor, we use a single-mode fiber and multimode welded micro-nano fiber as a substrate to deposit graphene oxide (GO) by natural deposition. We cover the surface of the micro-nano fiber by a temperature-sensitive material in order to increase the temperature

In this letter, we demonstrate the performance of the Tm:YLF and Tm:YAP slab lasers in free running. Both slab crystals are a-cut with a doping concentration of 3 at.%. Under an incident pump power of 376 W, maximum output powers of 130 and 126 W are obtained from the Tm:YLF and Tm:YAP lasers with the emissions peaks at 1909.4 and 1990.4 nm, respectively. The corresponding optical conversion efficiency

We study a continuous-wave sum-frequency blue laser operating at 484 nm. The laser elaborated is based on the intracavity pumping technology. A 912 nm laser produced by an end-pumped Nd:GdVO4 crystal, using an 808 nm fiber-coupled laser diode, is employed to pump an Yb:YAG crystal in the cavity to achieve the simultaneous oscillations in 912 and 1030 nm lasers. An intracavity sum-frequency achieved

Considering two mixed mechanical resonators, we investigate two different kinds of quantum correlations, i.e., entanglement and quantum discord. We use two Fabry–Pérot cavities coupled by squeezed light. To quantify entanglement and quantum discord, we employ respectively the Gaussian intrinsic entanglement and the Gaussian Hellinger discord. We found that these two forms of quantum correlations decay

Now it is indisputable fact that the Earth’s aerosphere contains Kolmogorov and non-Kolmogorov turbulence, which has been confirmed by increasing experimental evidences and theoretical investigations. Based on this, the scientific community conducts investigations on the combined influence of Kolmogorov turbulence and non-Kolmogorov one on optical wave propagating in the aerosphere. In this paper,

We present the influence of phase fluctuations on the entanglement and intensity of the radiation produced by a correlated-emission laser. The three-level atoms are initially prepared in a partial coherent superposition of the ground and exited states, and the driven radiation field incoming via the input mirror induces the atomic coherence that leads to the entanglement in the quantum system. The

In this work, we design a D-shaped photonic-crystal fiber (PCF) sensor with a large-hole self-reference channel based on the surface plasmon resonance. Using the numerical calculation method, we study variations of the transmission spectrum with concentration for the aqueous glucose solution. By optimizing the silver-film thickness of the reference and detected channels, we find that the sensitivity

We demonstrate a stable compact passively Q-switched laser generating 40 μJ, subnanosecond (< 1 ns) duration, 1064 nm pulses at a repetition rate of 10 kHz. With a composite Nd:YAG/Cr4+:YAG crystal in a simple and compact resonator end-pumped by intense 808 nm pulse, we effectively improve the stability of output laser pulses corresponding to the interpulse amplitude instability less 1% (rms) and the

The copper vapor laser (CVL) is the most powerful and efficient resonance metastable metal-vapor laser having widespread applications. Jitter requirements are very stringent when the CVL is operated in the oscillator–amplifier configuration. Jitter in the laser affects proper synchronization and thereby affects the output power and its stability. Although thyratron-based power supplies have low jitter

For Hermitian and non-Hermitian Hamiltonian matrices H, we present the Schr¨odinger equation for qudit (spin-j system, N-level atom) with the state vector |ψ〉 in a new form of the linear eigenvalue equation for the matrix ℋ = (H ⊗ 1N) and the probability eigenvector |p〉 identified with quantum states in the probability representation of quantum mechanics. We discuss the possibility to experimentally

We analyze the features of nonlinear refraction in colloidal solutions containing Ag2S quantum dots capped with thioglycolic acid (Ag2S/TGA) or L-cysteine (Ag2S/L-Cys), with the quantum-dot (QD) sizes ranging from 1.7 to 5.5 nm and their concentration in the solution being 0.1%. The Z-scans of the samples were obtained using 10 ns pulses of 532 nm radiation. For samples with various average sizes and

Based on the results of quantum field theory and quantum electrodynamics on virtual photons as quanta of electromagnetic interaction, we discuss the interpretation of quantum indeterminacy, uncertainty relations, and physics, which determine the probabilistic statistical character of quantum phenomena. We discuss the fundamental reasons for the appearance of the Planck constant in the uncertainty relations