Correlations of spin splitting and orbital fluctuations due to 1/f charge noise in the Si/SiGe Quantum Dot

Bibliographic Details
Title: Correlations of spin splitting and orbital fluctuations due to 1/f charge noise in the Si/SiGe Quantum Dot
Authors: Kępa, Marcin, Cywiński, Łukasz, Krzywda, Jan A.
Source: Appl. Phys. Lett. 123, 034003 (2023)
Publication Year: 2023
Collection: Condensed Matter
Subject Terms: Condensed Matter - Mesoscale and Nanoscale Physics
More Details: Fluctuations of electric fields can change the position of a gate-defined quantum dot in a semiconductor heterostructure. In the presence of magnetic field gradient, these stochastic shifts of electron's wavefunction lead to fluctuations of electron's spin splitting. The resulting spin dephasing due to charge noise limits the coherence times of spin qubits in isotopically purified Si/SiGe quantum dots. We investigate the spin splitting noise caused by such process caused by microscopic motion of charges at the semiconductor-oxide interface. We compare effects of isotropic and planar displacement of the charges, and estimate their densities and typical displacement magnitudes that can reproduce experimentally observed spin splitting noise spectra. We predict that for defect density of $10^{10}$ cm$^{-2}$, visible correlations between noises in spin splitting and in energy of electron's ground state in the quantum dot, are expected.
Comment: 6 pages, 4 figures, added repository: https://doi.org/10.24435/materialscloud:91-mj
Document Type: Working Paper
DOI: 10.1063/5.0156358
Access URL: http://arxiv.org/abs/2305.06011
Accession Number: edsarx.2305.06011
Database: arXiv
More Details
DOI:10.1063/5.0156358