Abstract
The synthesis of single-cycle pulses of compressed light and microwave signals sparked novel areas of fundamental research. In the field of acoustics, however, such a generation has not been introduced yet. For numerous applications, the large spatial extent of surface acoustic waves (SAW) causes unwanted perturbations and limits the accuracy of physical manipulations. Particularly, this restriction applies to SAW-driven quantum experiments with single flying electrons, where extra modulation renders the exact position of the transported electron ambiguous and leads to undesired spin mixing. Here, we address this challenge by demonstrating single-shot chirp synthesis of a strongly compressed acoustic pulse. Employing this solitary SAW pulse to transport a single electron between distant quantum dots with an efficiency exceeding 99%, we show that chirp synthesis is competitive with regular transduction approaches. Performing a time-resolved investigation of the SAW-driven sending process, we outline the potential of the chirped SAW pulse to synchronize single-electron transport from many quantum-dot sources. By superimposing multiple pulses, we further point out the capability of chirp synthesis to generate arbitrary acoustic waveforms tailorable to a variety of (opto)nanomechanical applications. Our results shift the paradigm of compressed pulses to the field of acoustic phonons and pave the way for a SAW-driven platform of single-electron transport that is precise, synchronized, and scalable.
5 More- Received 24 February 2022
- Revised 3 June 2022
- Accepted 11 July 2022
DOI:https://doi.org/10.1103/PhysRevX.12.031035
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Focus
Sound Pulse Drives Single-Electron Current
Published 7 September 2022
Like a surfer riding a wave, a single electron is transported by an acoustic pulse traveling along the surface of a microchip.
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Popular Summary
Sound waves provide a powerful platform to transport a single electron in nanoscale devices. Accordingly, they are highly promising to implement novel quantum-computing approaches where electrons are manipulated on the fly. Since sound waves typically consist of many periods, however, the implementation of such quantum logic is extremely challenging on a large scale. Here, we address this problem by engineering an acoustic wave that has a single surge—resembling a tidal bore at the nanoscale.
We employ a nonuniform transducer to compress many frequencies into an acoustic wave with a single peak. Letting a single electron surf on this acoustic wave front, we successively transport the elementary particle between distant nodes with an efficiency greater than 99%. In addition, we show that our technique enables formation of a solitary acoustic pulse with an arbitrary shape that is tailorable for a vast set of nanomechanical applications.
Since the acoustic pulse can successively pick up single electrons from multiple nodes, it provides a scalable innovation marking a paradigm shift for quantum-computing approaches.