论文标题
GD $^{3+}的强耦合到芯片超导谐振器
Strong coupling of a Gd$^{3+}$ multilevel spin system to an on-chip superconducting resonator
论文作者
论文摘要
我们报告说，在Scheelite（Cawo $ _4 $）的GD $^{3+} $旋转合奏之间实现了强耦合，而单晶的共振模式与共浮线超导型腔的共振模式，导致了146 MHz的Spin-Photon态分开。 Dicke模型和多级自旋系统的晶体场上哈密顿量很好地描述了这种相互作用。我们观察到由于腔中存在光子的存在，从而产生了晶体基态的明显扰动，因此观察到晶体场参数的变化。使用有限元计算，我们从数值估计腔传感量以及平均自旋耦合强度为$ g_0 \ $ 620 Hz。最后，通过记录腔度环信号作为脉冲长度和振幅的函数，通过脉冲测量值探索了自旋腔状态的动力学。结果表明，通过主动冷却过程以基础状态初始化此多级系统的潜在方法。
We report the realization of a strong coupling between a Gd$^{3+}$ spin ensemble hosted in a scheelite (CaWO$_4$) single crystal and the resonant mode of a coplanar stripline superconducting cavity leading to a large separation of spin-photon states of 146 MHz. The interaction is well described by the Dicke model and the crystal-field Hamiltonian of the multilevel spin system. We observe a change of the crystal-field parameters due to the presence of photons in the cavity that generates a significant perturbation of the crystal ground state. Using finite-element calculations, we numerically estimate the cavity sensing volume as well as the average spin-photon coupling strength of $g_0\approx$ 620 Hz. Lastly, the dynamics of the spin-cavity states are explored via pulsed measurements by recording the cavity ring-down signal as a function of pulse length and amplitude. The results indicate a potential method to initialize this multilevel system in its ground state via an active cooling process.
