论文标题
通过分散门传感表征的INSB双量子点中的可变和轨道依赖性自旋轨道场取向
Variable and orbital-dependent spin-orbit field orientations in a InSb double quantum dot characterized via dispersive gate sensing
论文作者
论文摘要
利用分散栅极传感（DGS），我们研究了旋转轨道字段（$ \ textbf {b} _ {so} $）方向在insb nanoWire中定义的多电子double量子点（dqd）中。在表征点间隧道耦合的同时，测得的分散信号取决于电子电荷占用率以及外部磁场的振幅和方向。当DQD被总奇数电子占据时，分散信号对外场方向不敏感。对于由总数量占据的DQD，当有限的外部磁场与有效的$ \ textbf {b} _ {so} $ entientation对齐时，分散信号会降低。这一事实可以识别$ \ textbf {b} _ {so} $方向的不同DQD电子占用。 $ \ textbf {b} _ {so} $方向在电荷过渡之间差异很大，通常既不垂直于纳米线也不垂直于芯片平面。此外，$ \ textbf {b} _ {so} $对于涉及相同价轨道的过渡对，并且在此类对之间有所不同。我们的工作证明了DG在表征量子点系统中自旋轨道相互作用的实用性，而无需任何电流流过设备。
Utilizing dispersive gate sensing (DGS), we investigate the spin-orbit field ($\textbf{B}_{SO}$) orientation in a many-electron double quantum dot (DQD) defined in an InSb nanowire. While characterizing the inter-dot tunnel couplings, the measured dispersive signal depends on the electron charge occupancy, as well as on the amplitude and orientation of the external magnetic field. The dispersive signal is mostly insensitive to the external field orientation when a DQD is occupied by a total odd number of electrons. For a DQD occupied by a total even number of electrons, the dispersive signal is reduced when the finite external magnetic field aligns with the effective $\textbf{B}_{SO}$ orientation. This fact enables the identification of $\textbf{B}_{SO}$ orientations for different DQD electron occupancies. The $\textbf{B}_{SO}$ orientation varies drastically between charge transitions, and is generally neither perpendicular to the nanowire nor in the chip plane. Moreover, $\textbf{B}_{SO}$ is similar for pairs of transitions involving the same valence orbital, and varies between such pairs. Our work demonstrates the practicality of DGS in characterizing spin-orbit interactions in quantum dot systems, without requiring any current flow through the device.
