论文标题
来自四极$^{73} $ ge的磁性梯度波动，仅si/sige交换量子
Magnetic Gradient Fluctuations from Quadrupolar $^{73}$Ge in Si/SiGe Exchange-Only Qubits
论文作者
论文摘要
我们使用交换回声噪声光谱研究研究了成对的Si/Sige量子点中的时触发磁梯度噪声机制。我们通过频谱反演和与理论建模的对应关系发现，$^{73} $ ge nuclei的四极动力在自旋回波衰减时间$ t_2 $中起着关键作用，具有对磁场的特征依赖性和SI量子良好的宽度。 $^{73} $ ge噪声峰出现在$^{73} $ ge larmor共振的基本和第一个谐波上，由于$^{29} $^{29} $ si Dipole-dipole动力学而被叠加到$ 1/f $噪声上，并且依赖于物质表现和应用磁场。这些结果可能会为使用Si/Sige量子点作为量子信息处理设备中的Qubits时的动态解耦需求。
We study the time-fluctuating magnetic gradient noise mechanisms in pairs of Si/SiGe quantum dots using exchange echo noise spectroscopy. We find through a combination of spectral inversion and correspondence to theoretical modeling that quadrupolar precession of the $^{73}$Ge nuclei play a key role in the spin-echo decay time $T_2$, with a characteristic dependence on magnetic field and the width of the Si quantum well. The $^{73}$Ge noise peaks appear at the fundamental and first harmonic of the $^{73}$Ge Larmor resonance, superimposed over $1/f$ noise due to $^{29}$Si dipole-dipole dynamics, and are dependent on material epitaxy and applied magnetic field. These results may inform the needs of dynamical decoupling when using Si/SiGe quantum dots as qubits in quantum information processing devices.
