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arXiv · 2106.14684

The emergent linear Rashba spin-orbit coupling offering the fast manipulation of hole-spin qubits in germanium

Yang Liu·Jia-Xin Xiong·Zhi Wang·Wen-Long Ma·Shan Guan·Jun-Wei Luo·Shu-Shen Li
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Abstract

The electric dipole spin resonance (EDSR) combining strong spin-orbit coupling (SOC) and electric-dipole transitions facilitates fast spin control in a scalable way, which is the critical aspect of the rapid progress made recently in germanium (Ge) hole-spin qubits. However, a puzzle is raised because centrosymmetric Ge lacks the Dresselhaus SOC, a key element in the initial proposal of the hole-based EDSR. Here, we demonstrate that the recently uncovered finite k-linear Rashba SOC of 2D holes offers fast hole spin control via EDSR with Rabi frequencies in excellent agreement with experimental results over a wide range of driving fields. We also suggest that the Rabi frequency can reach 500 MHz under a higher gate electric field or multiple GHz in a replacement by [110]oriented wells. These findings bring a deeper understanding for hole-spin qubit manipulation and offer design principles to boost the gate speed.

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Yang Liu, Jia-Xin Xiong, Zhi Wang, Wen-Long Ma, Shan Guan, Jun-Wei Luo, Shu-Shen Li. 2021-06-28. The emergent linear Rashba spin-orbit coupling offering the fast manipulation of hole-spin qubits in germanium. https://doi.org/10.1103/physrevb.105.075313

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