论文标题
部分可观测时空混沌系统的无模型预测
Coherent spin dynamics of rare-earth doped crystals in the high-cooperativity regime
论文作者
论文摘要
稀土掺杂晶体的连贯性时间很长，并且具有在微波和光光子之间提供量子接口的潜力。这种应用受益于自旋整体和微波腔之间的高协作性 - 这激发了稀土离子浓度的增加，从而影响自旋相干寿命。我们测量了两种稀土旋转物种的自旋动力学，$^{145} $ nd和yb掺入y $ _ {2} $ sio $ _ {5} $，在高度合作式的平面微波谐波谐振器中，在温度范围为1.2 k至14 Mk的温度范围内。我们确定了相关的破坏机制，包括偶然的旋转以及与环境中杂质电子和核自旋相互依赖的光谱扩散产生的瞬时扩散。我们探索了两种方法，以减轻低温极限中YB系统中光谱扩散的影响，首先是使用最多1 t的磁场来抑制杂质自旋动力学，其次使用具有低有效G系数的跃迁来降低对这种动力学的敏感性。最后，我们演示了零字段的$^{171} $ yb系统中存在的“时钟过渡”如何将连贯时间提高到$ t_ {2} = 6（1）$ ms。
Rare-earth doped crystals have long coherence times and the potential to provide quantum interfaces between microwave and optical photons. Such applications benefit from a high cooperativity between the spin ensemble and a microwave cavity -- this motivates an increase in the rare earth ion concentration which in turn impacts the spin coherence lifetime. We measure spin dynamics of two rare-earth spin species, $^{145}$Nd and Yb doped into Y$_{2}$SiO$_{5}$, coupled to a planar microwave resonator in the high cooperativity regime, in the temperature range 1.2 K to 14 mK. We identify relevant decoherence mechanisms including instantaneous diffusion arising from resonant spins and temperature-dependent spectral diffusion from impurity electron and nuclear spins in the environment. We explore two methods to mitigate the effects of spectral diffusion in the Yb system in the low-temperature limit, first, using magnetic fields of up to 1 T to suppress impurity spin dynamics and, second, using transitions with low effective g-factors to reduce sensitivity to such dynamics. Finally, we demonstrate how the `clock transition' present in the $^{171}$Yb system at zero field can be used to increase coherence times up to $T_{2} = 6(1)$ ms.
