New studies on the g-factors of 1D holes on GaAs quantum point contacts

Add to your list(s) Download to your calendar using vCal

• Karina Hudson, University of New South Wales
• Friday 16 June 2017, 14:15-15:15
• Mott Seminar Room (Mott Building Room 531), Cavendish Laboratory.

If you have a question about this talk, please contact Dr Joanna Waldie.

A complete description of the spin response of 1D holes in quantum point contacts (QPCs) has remained an outstanding problem in spintronics. Despite this being a simple one-dimensional non-interacting problem, for 10 years no single theory has been been able to model the gzz >> g|| >> gperp form of the g-tensor seen time and again in Zeeman spin-splitting measurements on hole QPCs. However, newly developed theory from Dmitry Miserev et. al. on 1D holes in QPCs predicts that g|| is insensitive to Rashba, while gperp is highly sensitive. This model has successfully described the g-factor measured via Zeeman spin-splitting measurements for QPCs on quantum well (100) wafers [1], and is a promising candidate for explaining spin-behaviour in single heterojunction wafers with a strong Rashba field. In order to fully explore the effect of Rashba field on 1D holes, we are hoping to fabricate hole QPC devices on Cambridge wafer with an in-situ backgate in the very near future, which is an ongoing project with Dr. Joanna Waldie and the MBE growers at the Cavendish Laboratory. We have also started measuring Zeeman spin-splitting on p-type (111) GaAs wafer, where Rashba and Dresselhaus terms are predicted to anti-align and cause a suppression in the effective magnetic field, resulting in novel spin-behaviour [2].

[1] D. Miserev, et. al. arXiv:1612.00572 [cond-mat.mes-hall]

[2] L.Wang and M.W.Wu, Phys. Rev. B. 85, 235308 (2012)

This talk is part of the Semiconductor Physics Group Seminars series.

This talk is included in these lists:

• All Cavendish Laboratory Seminars
• All Talks (aka the CURE list)
• Centre for Health Leadership and Enterprise
• Featured lists
• ME Seminar
• Mott Seminar Room (Mott Building Room 531), Cavendish Laboratory
• Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
• School of Physical Sciences
• Semiconductor Physics Group Seminars
• Thin Film Magnetic Talks

Note that ex-directory lists are not shown.