de Paula Marcos V S, Sinesio William W T, Dodonov Alexandre V
Institute of Physics, University of Brasilia, Caixa Postal 04455, Brasilia 70910-900, DF, Brazil.
International Center of Physics, Institute of Physics, University of Brasilia, Brasilia 70910-900, DF, Brazil.
Entropy (Basel). 2023 Jun 6;25(6):901. doi: 10.3390/e25060901.
We propose a scheme for the generation of photons from a vacuum via time-modulation of a quantum system indirectly coupled to the cavity field through some ancilla quantum subsystem. We consider the simplest case when the modulation is applied to an artificial two-level atom (we call 't-qubit', that can be located even outside the cavity), while the ancilla is a stationary qubit coupled via the dipole interaction both to the cavity and t-qubit. We find that tripartite entangled states with a small number of photons can be generated from the system ground state under resonant modulations, even when the t-qubit is far detuned from both the ancilla and the cavity, provided its bare and modulation frequencies are properly adjusted. We attest our approximate analytic results by numeric simulations and show that photon generation from vacuum persists in the presence of common dissipation mechanisms.
我们提出了一种通过对量子系统进行时间调制来从真空中产生光子的方案，该量子系统通过某个辅助量子子系统间接耦合到腔场。我们考虑最简单的情况，即调制应用于一个人造二能级原子（我们称之为“t - 量子比特”，它甚至可以位于腔外），而辅助系统是一个通过偶极相互作用与腔和t - 量子比特都耦合的稳态量子比特。我们发现，即使t - 量子比特与辅助系统和腔都有很大失谐，只要其裸频率和调制频率得到适当调整，在共振调制下，系统基态就能产生少量光子的三方纠缠态。我们通过数值模拟验证了我们的近似解析结果，并表明在存在常见耗散机制的情况下，真空中的光子产生仍然存在。
