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arXiv · 1708.06278

Fast Hole Tunneling Times in Germanium Hut Wires Probed by Single-Shot Reflectometry

Lada Vukušić·Josip Kukučka·Hannes Watzinger·Georgios Katsaros
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Abstract

Heavy holes confined in quantum dots are predicted to be promising candidates for the realization of spin qubits with long coherence times. Here we focus on such heavy-hole states confined in Germanium hut wires. By tuning the growth density of the latter we can realize a T-like structure between two neighboring wires. Such a structure allows the realization of a charge sensor, which is electrostatically and tunnel coupled to a quantum dot, with charge-transfer signals as high as 0.3e. By integrating the T-like structure into a radio-frequency reflectometry setup, single-shot measurements allowing the extraction of hole tunneling times are performed. The extracted tunneling times of less than 10$\mu$s are attributed to the small effective mass of Ge heavy-hole states and pave the way towards projective spin readout measurements.

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Lada Vukušić, Josip Kukučka, Hannes Watzinger, Georgios Katsaros. 2017-08-21. Fast Hole Tunneling Times in Germanium Hut Wires Probed by Single-Shot Reflectometry. https://doi.org/10.1021/acs.nanolett.7b02627

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