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arXiv · 2001.11305

Self-controlled growth of highly uniform Ge/Si hut wires for scalable qubit devices

Fei Gao·Jian-Huan Wang·Hannes Watzinger·Hao Hu·Marko J. Rančić·Jie-Yin Zhang·Ting Wang·Yuan Yao·Gui-Lei Wang·Josip Kukučka·Lada Vukušić·Christoph Kloeffel·Daniel Loss·Feng Liu·Georgios Katsaros·Jian-Jun Zhang
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Abstract

Semiconductor nanowires have been playing a crucial role in the development of nanoscale devices for the realization of spin qubits, Majorana fermions, single photon emitters, nanoprocessors, etc. The monolithic growth of site-controlled nanowires is a prerequisite towards the next generation of devices that will require addressability and scalability. Here, combining top-down nanofabrication and bottom-up self-assembly, we report on the growth of Ge wires on pre-patterned Si (001) substrates with controllable position, distance, length and structure. This is achieved by a novel growth process which uses a SiGe strain-relaxation template and can be generalized to other material combinations. Transport measurements show an electrically tunable spin-orbit coupling, with a spin-orbit length similar to that of III-V materials. Also, capacitive coupling between closely spaced wires is observed, which underlines their potential as a host for implementing two qubit gates. The reported results open a path towards scalable qubit devices with Si compatibility.

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Fei Gao, Jian-Huan Wang, Hannes Watzinger, Hao Hu, Marko J. Rančić, Jie-Yin Zhang, Ting Wang, Yuan Yao, Gui-Lei Wang, Josip Kukučka, Lada Vukušić, Christoph Kloeffel, Daniel Loss, Feng Liu, Georgios Katsaros, Jian-Jun Zhang. 2020-01-30. Self-controlled growth of highly uniform Ge/Si hut wires for scalable qubit devices. https://doi.org/10.1002/adma.201906523

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