论文标题
关键Kerr谐振器中电流波动的分歧
Diverging current fluctuations in critical Kerr resonators
论文作者
论文摘要
参数泵送的KERR模型描述了一个驱动的非线性非线性腔，其非平衡相图具有连续和不连续的量子相变。我们考虑这些关键现象的后果是通过腔内连续弱测量获得的光电流波动的波动。考虑到直接的光检测和同伴检测方案，我们发现当前的波动在不连续的相变时呈指数差异。但是，我们发现这两个检测方案在连续过渡附近的这两个检测方案中发生了明显不同的电流波动，这种行为是由不同碱基中测量结果揭示的互补信息来解释的。为了获得这些结果，我们开发公式以有效计算直接来自量子主方程的扩散系数（以长期电流波动为特征），从而连接完整计数统计量和随机量子轨迹的形式主义。我们的发现突出了量子光系统中非平衡相变的当前波动的丰富特征。
The parametrically pumped Kerr model describes a driven-dissipative nonlinear cavity, whose nonequilibrium phase diagram features both continuous and discontinuous quantum phase transitions. We consider the consequences of these critical phenomena for the fluctuations of the photocurrent obtained via continuous weak measurements on the cavity. Considering both direct photodetection and homodyne detection schemes, we find that the current fluctuations diverge exponentially at the discontinuous phase transition. However, we find strikingly different current fluctuations for these two detection schemes near the continuous transition, a behaviour which is explained by the complementary information revealed by measurements in different bases. To obtain these results, we develop formulas to efficiently compute the diffusion coefficient -- which characterises the long-time current fluctuations -- directly from the quantum master equation, thus connecting the formalisms of full counting statistics and stochastic quantum trajectories. Our findings highlight the rich features of current fluctuations near nonequilibrium phase transitions in quantum-optical systems.
