Dissipative dynamics in a tunable Rabi dimer with periodic harmonic driving

Abstract

Recent progress on qubit manipulation allows application of periodic driving signals on qubits. In this study, a harmonic driving field is added to a Rabi dimer to engineer photon and qubit dynamics in a circuit quantum electrodynamics device. To model environmental effects, qubits in the Rabi dimer are coupled to a phonon bath with a sub-Ohmic spectral density. A non-perturbative treatment, the Dirac-Frenkel time-dependent variational principle together with the multiple Davydov D2 Ansatz is employed to explore the dynamical behavior of the tunable Rabi dimer. In the absence of the phonon bath, the amplitude damping of the photon number oscillation is greatly suppressed by the driving field, and photons can be created thanks to resonances between the periodic driving field and the photon frequency. In the presence of the phonon bath, one still can change the photon numbers in two resonators, and indirectly alter the photon imbalance in the Rabi dimer by directly varying the driving signal in one qubit. It is shown that qubit states can be manipulated directly by the harmonic driving. The environment is found to strengthen the interqubit asymmetry induced by the external driving, opening up a new venue to engineer the qubit states. arXiv:1905.06272v1 [quant-ph]

Variational approach to time-dependent fluorescence of a driven qubit

“…The present formalism is capable of treating relatively complicated models of interest in quantum optics. For instance, we can extend the ansatz to study bosonic dynamics when multiple emitters interact with a common bath [42]. We can also study the bosonic dynamics when two bosonic baths interact with an emitter.…”

Schrödinger-cat states in Landau-Zener-Stückelberg-Majorana interferometry: a multiple Davydov Ansatz approach

“…72 Recently it has also been found that the states of qubits and photons in a complex Rabi-dimer system can be engineered by driving the qubits with sinusoidal fields. 73,74 Detailed dynamics related to those multiple LZ transitions has not been well understood, as it is a nontrivial task to analyze the coupled qubit-photon dynamics at LZ transitions. In this section, we present an in-depth analysis of the qubit-photon dynamics at multiple LZ transitions by depicting the population dynamics in individual coupled qubit-photon states.…”

Photon-assisted Landau-Zener transitions in a periodically driven Rabi dimer coupled to a dissipative mode

“…The multi-D 2 Ansatz has been employed to study static properties and dynamic processes in a variety of toy models and realistic systems, demonstrating excellent numerical efficiency and accuracy in a broad parameter regime in the presence of both diagonal and off-diagonal systembath couplings [39,53,55,59,[61][62][63]. Previous studies have also demonstrated the suitability and accuracy of the multi-D 2 Ansatz for similar driven QED systems [38]. In order to tackle both diagonal qubit-phonon and the off-diagonal qubit-photon interactions in the hybrid photon-qubit-phonon system in this work, we construct the following multi-D 2 Ansatz with multiplicity M as a superposition of M copies of the single Davydov D 2 Ansatz…”

“…By cal-culating time-averaged photon imbalance under different qubit-photon coupling strengths and photon tunneling rates, they discovered three photonic phases [36]. Recently the effects of a phonon environment and an external driving field on the dynamics of qubits and photons in the Rabi dimer have been elucidated in various parameter regimes using the time-dependent variational principle with the multiple Davydov D 2 Ansatz [37,38]. However, the LZ transitions and their susceptibility to environmental effects in this Rabi dimer system have not been well investigated, in contrast to systematically studied LZ transitions in single-qubit QED devices.…”