论文标题
驱动的耗散玻色 - 哈伯德模型的时间和频域两粒子相关性
Time- and frequency-domain two-particle correlations of a driven dissipative Bose-Hubbard model
论文作者
论文摘要
我们从理论上研究了耗散散发相关驱动的散发性散发器式 - 哈伯德模型(BHM)的时间和频域两粒子相关性。我们计算汉伯里·布朗 - 尤里斯(HBT)型两粒子时间相关函数$ g^2(τ)$,作为时间延迟$τ$的函数,它显示了振荡,其频率由liouvillian Gap的假想部分确定。当差距靠近过渡点时,该点的振荡消失了。对于远离过渡点的参数,HBT相关性显示从超级束缚到反束式制度的振荡。我们表明,HBT相关性向频域的傅立叶变换提供了有关DPT和Liouvillian动力学的信息。我们从数值上求解了多体的lindblad主方程,并计算系统以稳态状态的智慧分布来确定dpt。below below某些驱动强度,傅立叶变换显示了两峰结构,而高于该强度的强度则表现出洛伦兹(Lorenzian)类似洛伦兹(Lorenzian)的单峰结构或带有两次下降的结构。单峰结构的宽度在相变点处最小,并且该结构的峰值始终位于零频率。在两峰结构的情况下,两个对称峰的位置由liouvillian间隙的假想部分给出,而它们的一半最大宽度(HWHM)由间隙的实际部分给出。两个下降的位置和宽度也与Liouvillian操作员的低谎言特征值有关。我们根据HBT相关函数及其傅立叶变换讨论模型的量子统计特性。
We theoretically investigate the time- and frequency-domain two-particle correlations of a driven dissipative Bose-Hubbard model (BHM) at and near a dissipative phase transition (DPT). We compute Hanbury Brown-Twiss (HBT) type two-particle temporal correlation function $g^2(τ)$ which, as a function of time delay $τ$, exhibits oscillations with frequencies determined by the imaginary part of Liouvillian gap. As the gap closes near a transition point, the oscillations at that point dies down. For parameters slightly away from the transition point, the HBT correlations show oscillations from super-bunching to anti-bunching regimes. We show that the Fourier transform of HBT correlations into frequency domain provide information about DPT and Liouvillian dynamics. We numerically solve the many-body Lindblad master equation and calculate Wigner distribution of the system in steady state to ascertain DPT.Below certain drive strength, the Fourier transform shows a two-peak structure while above that strength it exhibits either a Lorenzian-like single-peak structure or a structure with two-dips. The width of the single-peak structure is minimum at the phase transition point and the peak of this structure always lies at zero frequency. The positions of the two symmetrical peaks in case of two-peak structure are given by the imaginary parts of the Liouvillian gap while their half width at half maximum (HWHM) is given by the real part of the gap. The positions and the widths of the two dips are also related to low lying eigenvalues of the Liouvillian operator. We discuss quantum statistical properties of the model in terms of the HBT correlation function and its Fourier transform.