Fast hole tunneling times in germanium hut wires probed by single-shot reflectometry Journal Article

Author(s): Vukušić, Lada; Kukučka, Josip; Watzinger, Hannes; Katsaros, Georgios
Article Title: Fast hole tunneling times in germanium hut wires probed by single-shot reflectometry
Affiliation IST Austria
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 μs are attributed to the small effective mass of Ge heavy-hole states and pave the way toward projective spin readout measurements.
Keywords: quantum dot; Germanium; heavy hole; reflectometry; single-shot measurement
Journal Title: Nano Letters
ISSN: 1530-6992
Publisher: American Chemical Society  
Date Published: 2017-08-10
Copyright Statement: CC BY
DOI: 10.1021/acs.nanolett.7b02627
Notes: The work was financially supported by the ERC Starting Grant no. 335497 project and the FWF-Y 715-N30 project. Weacknowledge Thomas Watson for helpful discussions and F. Schaffler for fruitful discussions related to the HW growth and for giving us access to the molecular beam epitaxy system. This research was supported by the Scientific Service Units (SSU) of IST Austria through resources provided by the MIBA Machine Shop. In particular, we acknowledge T. Asenov, T. Adeltzberger, T. Menner, and P. Traunmuller.
Open access: yes (OA journal)