论文标题
基于测量的量子系统基于测量的反馈控制
Measurement-based Feedback Control of a Quantum System in a Harmonic Potential
论文作者
论文摘要
我们提出了一个空间维度中单个量子粒子的基于测量的反馈控制的公式。连续监测粒子位置和动量的任意线性组合，并使用与测量信号成比例的反馈来控制系统。我们得出反馈主方程，并讨论一种计算稳态解决方案的一般方法。对于量子谐波振荡器或自由粒子，我们表明可以使用同时抑制可观察到的可观察到的可观察到的反馈冷却和局限系统，并补偿测量引入的噪声。此外，我们证明了适当的反馈在系统的哈密顿量中可观察到的二次术语。对于谐波电位的特定情况，我们描述了可以冷却至基态的系统的确切动力学。此外，我们提供了一个论点，说明测量足够强，足以将粒子定位在小于电势的特征长度尺度的间隔上，就可以使粒子定位的粒子定位。
We present a formulation of measurement-based feedback control of a single quantum particle in one spatial dimension. An arbitrary linear combination of the position and momentum of the particle is continuously monitored, and feedback proportional to the measured signal is used to control the system. We derive a feedback master equation and discuss a general approach to computing the steady-state solutions for arbitrary potentials. For a quantum harmonic oscillator or a free particle, we show that it is possible to cool and confine the system using feedback that simultaneously damps the measured observable and its conjugate momentum, as well as compensates for noise introduced by the measurement. In addition, we demonstrate that appropriate feedback adds a quadratic term in the measured observable to the Hamiltonian of the system. For the particular case of the harmonic potential, we describe the exact dynamics of the system that can be cooled to the ground state. Moreover, we provide an argument for the possibility to cool systems with arbitrary potentials provided that the measurement is strong enough to localise the particle on an interval smaller than the characteristic length scale of the potential.
