论文标题
快速冷却牢固的边带耦合方案中的被困离子
Fast Cooling of Trapped Ion in Strong Sideband Coupling Regime
论文作者
论文摘要
用羔羊dicke参数$η\ ll1 $在羔羊dicke方案中被困的离子可以使用边带冷却冷却至其运动基态。标准边带冷却在弱边带耦合极限下起作用，与内部激发状态的天然线宽$γ$相比，边带耦合强度很小，冷却速率小于$γ$。在这里，我们考虑强大的边带耦合方案中的冷却方案，其中边带耦合强度可比甚至大于$γ$。我们得出了该机构中的冷却速率和运动稳态平均职业的分析表达式，我们表明，与$γ$成正比的冷却速率相比，与$η^{2} $相比，稳态占用率与$γ$成正比。我们通过数值模拟证明我们的分析表达式忠实地恢复了强侧带耦合方案中的确切动力学。
Trapped ion in the Lamb-Dicke regime with the Lamb-Dicke parameter $η\ll1$ can be cooled down to its motional ground state using sideband cooling. Standard sideband cooling works in the weak sideband coupling limit, where the sideband coupling strength is small compared to the natural linewidth $γ$ of the internal excited state, with a cooling rate much less than $γ$. Here we consider cooling schemes in the strong sideband coupling regime, where the sideband coupling strength is comparable or even greater than $γ$. We derive analytic expressions for the cooling rate and the average occupation of the motional steady state in this regime, based on which we show that one can reach a cooling rate which is proportional to $γ$, while at the same time the steady state occupation increases by a correction term proportional to $η^{2}$ compared to the weak sideband coupling limit. We demonstrate with numerical simulations that our analytic expressions faithfully recover the exact dynamics in the strong sideband coupling regime.
