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arXiv · 2206.03653

Gate-Tunable Spin-Orbit Coupling in a Germanium Hole Double Quantum Dot

He Liu·Ting Zhang·Ke Wang·Fei Gao·Gang Xu·Xin Zhang·Shu-Xiao Li·Gang Cao·Ting Wang·Jianjun Zhang·Xuedong Hu·Hai-Ou Li·Guo-Ping Guo
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Abstract

Hole spins confined in semiconductor quantum dot systems have gained considerable interest for their strong spin-orbit interactions (SOIs) and relatively weak hyperfine interactions. Here we experimentally demonstrate a tunable SOI in a double quantum dot in a Germanium (Ge) hut wire (HW), which could help enable fast all-electric spin manipulations while suppressing unwanted decoherence. Specifically, we measure the transport spectra in the Pauli spin blockade regime in the double quantum dot device.By adjusting the interdot tunnel coupling, we obtain an electric field tuned spin-orbit length lso = 2.0 - 48.9 nm. This tunability of the SOI could pave the way toward the realization of high-fidelity qubits in Ge HW systems.

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He Liu, Ting Zhang, Ke Wang, Fei Gao, Gang Xu, Xin Zhang, Shu-Xiao Li, Gang Cao, Ting Wang, Jianjun Zhang, Xuedong Hu, Hai-Ou Li, Guo-Ping Guo. 2022-06-08. Gate-Tunable Spin-Orbit Coupling in a Germanium Hole Double Quantum Dot. https://doi.org/10.1103/physrevapplied.17.044052

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