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

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 0.3 e. By integrating the T-like structure into a radiofrequency reflectometry setup, single-shot measurements allowing the extraction of hole tunneling times are performed. The extracted tunneling times of less than 10 ?s are attributed to the small effective mass of Ge heavy-hole states and pave the way toward projective spin readout measurements.

SUBMITTER: Vukusic L

PROVIDER: S-EPMC5599875 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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

Vukušić Lada L Kukučka Josip J Watzinger Hannes H Katsaros Georgios G

Nano letters 20170821 9

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 0.3 e. By integ ...[more]

PMID: 28795821

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