Struck, Tom and Hollmann, Arne and Schauer, Floyd and Fedorets, Olexiy and Schmidbauer, Andreas and Sawano, Kentarou and Riemann, Helge and Abrosimov, Nikolay V. and Cywinski, Lukasz and Bougeard, Dominique and Schreiber, Lars R. (2020) Low-frequency spin qubit energy splitting noise in highly purified Si-28/SiGe. NPJ QUANTUM INFORMATION, 6 (1): 40. ISSN , 2056-6387
Full text not available from this repository. (Request a copy)Abstract
We identify the dominant source for low-frequency spin qubit splitting noise in a highly isotopically-purified silicon device with an embedded nanomagnet and a spin echo decay time T-2(echo) = 128 mu s. The power spectral density (PSD) of the charge noise explains both, the clear transition from a 1/f(2)- to a 1/f-dependence of the splitting noise PSD as well as the experimental observation of a decreasing time-ensemble spin dephasing time, from T-2* approximate to 20 mu s, with increasing measurement time over several hours. Despite their strong hyperfine contact interaction, the few Ge-73 nuclei overlapping with the quantum dot in the barrier do not limit T-2*, likely because their dynamics is frozen on a few hours measurement scale. We conclude that charge noise and the design of the gradient magnetic field are the key to further improve the qubit fidelity in isotopically purified Si-28/SiGe.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | SINGLE-ELECTRON SPIN; QUANTUM; SILICON; RESONANCE; GATE; |
| Subjects: | 500 Science > 530 Physics |
| Divisions: | Physics > Institute of Experimental and Applied Physics > Chair Professor Huber > Group Dominique Bougeard |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 24 Mar 2021 10:08 |
| Last Modified: | 24 Mar 2021 10:08 |
| URI: | https://pred.uni-regensburg.de/id/eprint/44557 |
Actions (login required)
 |
View Item |
