Quantum dynamics of acoustical phonon statistics

Andrew N. Cleland

M. Bagheri Harouni

A microscopic theory to study the combined dynamics of a quantum dot exciton coupled to a single cavity mode as well as acoustic phonons is presented. By considering the phonon subsystem in the coherent state representation, the phonon’s impact on the emitted photons is investigated. The single photon emission probability and phonon effects on this quantity are studied. On the other hand, we illustrate that while a quantum dot interacts with a single cavity mode, the collapse and revival phenomenon will occur. It is demonstrated that acoustic phonons have a pronounced impact on the collapse and revival of the quantum dot exciton. Our finding reveals that at elevated temperatures the phonon interaction decreases the Rabi frequency. Moreover, the cavity mode possesses non-classical features such as sub-Poissonian statistics.

Kevin J. Satzinger, Y. P. Zhong, H.-S. Chang +14 more

Robert J. Schoelkopf

Tai-Shuang Yin, Guangri Jin, Aixi Chen

We propose a scheme to implement the phonon antibunching and phonon blockade in a circuit quantum acoustodynamical system containing two surface acoustic wave (SAW) resonators coupled to a superconducting qubit. In the cases of driving only one SAW resonator and two SAW resonators, we investigate the phonon statistics by numerically calculating the second-order correlation function. It is found that, when only one SAW cavity is resonantly driven, the phonon antibunching effect can be achieved even when the qubit-phonon coupling strength is smaller than the decay rates of acoustic cavities. This result physically originates from the quantum interference between super-Poissonian statistics and Poissonian statistics of phonons. In particular, when the two SAW resonators are simultaneously driven under the mechanical resonant condition, the phonon antibunching effect can be significantly enhanced, which ultimately allows for the generation of a phonon blockade. Moreover, the obtained phonon blockade can be optimized by regulating the intensity ratio of the two SAW driving fields. In addition, we also discuss in detail the effect of system parameters on the phonon statistics. Our work provides an alternative way for manipulating and controlling the nonclassical effects of SAW phonons. It may inspire the engineering of new SAW-based phonon devices and extend their applications in quantum information processing.

shifa liu

We develop quantum acoustics as an independent quantum discipline. The elementary bosonic quantum is the phonon, obtained by canonical quantization of the elastic displacement field of a medium. The central replacement is c → cs, ε0 → ρ0, μ0 → 1/K, ℏ → ℏ, while the Planck constant is not replaced. Phonons obey canonical commutation relations, Bose–Einstein statistics with vanishing chemical potential, and energy quantization E = ℏω. The optical–acoustic dictionary is exact at the level of canonical quantization, mode algebra, Fock, coherent, squeezed, thermal and entangled states, and at the level of linear interference in the long-wavelength, single-branch, dissipationless limit. Multi-branch, dispersive, dissipative and finite-lifetime effects are handled by the generalized dictionary stated in Chapter 56. Quantum acoustics contains a macroscopic quantum branch, but it is not identical to macro- scopic quantum mechanics. The manuscript covers classical elasticity, variational principles, canonical quantization, phonon field algebra, propagators, Green functions, wave–particle duality, Bose–Einstein statistics, blackbody radiation, Debye heat capacity, acoustic quantum constants, acoustic Bekenstein–Hawking entropy, phonon thermodynamics, phonon BEC, phonon lasers, superfluidity, Fock, coherent, squeezed, thermal, entangled and non-classical states, beam splitters, Mach–Zehnder interferometers, Fabry–Perot cavities, Hong–Ou–Mandel interference, second-order coherence, phonon qubits, single- and two-qubit gates, quantum algorithms, quantum error correction and surface-code thresholds, quantum computing architecture, quantum networks and repeaters, quantum simulation, quantum sensing, topological phononic crystals, the SSH phonon model, two-dimensional topological phononic insulators, three-dimensional phonon Weyl semimetals, non-Hermitian acoustics and the phonon skin effect, non-Bloch band theory, topological defect classification, acoustic metrics, acoustic horizons, acoustic Hawking radiation, acoustic black- hole entropy and the information paradox, acoustic cosmology, phonon–graviton mixing, gravitational-wave coupling, the phonon analogy of dark matter and dark energy, surface acoustic wave resonators, optomechanical systems, superconducting qubit–phonon hybrid systems, Bose–Einstein condensates, phononic crystals, acoustic metamaterials, gravitational-wave detectors, the complete optical–acoustic dictionary, the generalized dictionary for multi-branch, dispersive, dissipative and finite-lifetime phonons, and strong-field QED vacuum and media as an analogue of multi-refringent, dispersive and dissipative media. Acoustic Hawking radiation has been observed in Bose–Einstein condensates by Steinhauer (2016). All definitions, derivations, mathematical details, experimental proposals and comparison factors are presented with explicit assumptions and complete proofs.