论文标题
在强光耦合中真空波动的平均场地处理
A Mean-Field Treatment of Vacuum Fluctuations in Strong Light-Matter Coupling
论文作者
论文摘要
平均场混合量子 - 古典动力学可以通过经典地描述光场及其真空波动来提供急需的量子模型。然而，当光 - 耦合变得强烈时，已知这种方法会遭受能量从真空波动中的非物理转移。我们强调了这个问题的光腔中原子的情况，并通过引入一组其他经典坐标来解决该问题，以特异性地表示真空波动，其光线相互作用由原子的瞬时地面种群缩放。这不仅严格防止上述非物理能量转移，而且还证明可以在原子种群和光场动力学方面产生从根本上提高的精度，从而与完整的量子计算产生了极好的一致性。因此，最终的方法是一种有吸引力的解决方案，用于实现涉及宏观数量的光学模式的强光 - 耦合现象的负担得起的建模。
Mean-field mixed quantum--classical dynamics could provide a much-needed means to inexpensively model quantum electrodynamical phenomena, by describing the optical field and its vacuum fluctuations classically. However, this approach is known to suffer from an unphysical transfer of energy out of the vacuum fluctuations when the light--matter coupling becomes strong. We highlight this issue for the case of an atom in an optical cavity, and resolve it by introducing an additional set of classical coordinates to specifically represent vacuum fluctuations whose light--matter interaction is scaled by the instantaneous ground-state population of the atom. This not only rigorously prevents the aforementioned unphysical energy transfer, but is also shown to yield a radically improved accuracy in terms of the atomic population and the optical field dynamics, generating results in excellent agreement with full quantum calculations. As such, the resulting method emerges as an attractive solution for the affordable modeling of strong light--matter coupling phenomena involving macroscopic numbers of optical modes.
