论文标题
耦合到热真空的游离棕色粒子的能量
Energy of a free Brownian particle coupled to thermal vacuum
论文作者
论文摘要
实验者的温度非常接近绝对零，曾经是普通的物理学变得非同寻常。在这样的政权中，量子效应和波动开始起主要作用。在这种情况下，我们研究了最简单的开放量子系统，即一种自由量子布朗尼粒子与热真空结合的，即在绝对零温度的极限情况下的恒温器。我们分析了粒子和热真空之间的平均能量$ e = e（c）$从弱相互作用强度$ c $。考虑了各种耗散机制的影响。在弱耦合方案中，能量趋于零为$ e（c）\ sim c \，\ ln {（1/c）} $，而在强耦合方案中，它以$ e（c）\ sim \ sim \ sqrt {c} $的差异为无穷大。我们为此证明了这是由广义Langevin方程的内存内核$γ（t）$定义的耗散机制的选定示例。我们揭示了固定价值的$ c $如何取决于耗散模型：必须比较耗散函数$γ（t）$的衍生$γ'（t）$的值$γ（t）$在时间$ t = 0 $或在内存时间$ t =τ_c$，以表征非乳化性棕色粒子粒子动态的程度。还提出了低温的影响。
Experimentalists have come to temperatures very close to absolute zero at which physics that was once ordinary becomes extraordinary. In such a regime quantum effects and fluctuations start to play a dominant role. In this context we study the simplest open quantum system, namely, a free quantum Brownian particle coupled to thermal vacuum, i.e. thermostat in the limiting case of absolute zero temperature. We analyze the average energy $E=E(c)$ of the particle from a weak to strong interaction strength $c$ between the particle and thermal vacuum. The impact of various dissipation mechanisms is considered. In the weak coupling regime the energy tends to zero as $E(c) \sim c\, \ln{(1/c)}$ while in the strong coupling regime it diverges to infinity as $E(c) \sim \sqrt{c}$. We demonstrate it for selected examples of the dissipation mechanisms defined by the memory kernel $γ(t)$ of the Generalized Langevin Equation. We reveal how at a fixed value of $c$ the energy $E(c)$ depends on the dissipation model: one has to compare values of the derivative $γ'(t)$ of the dissipation function $γ(t)$ at time $t=0$ or at the memory time $t=τ_c$ which characterizes the degree of non-Markovianity of the Brownian particle dynamics. The impact of low temperature is also presented.
