Quantum Electronic Devices

Welcome to the web page of the Quantum Electronic Devices group in UNSW's School of Physics

The Quantum Electronic Devices group is part of the Condensed Matter department in UNSW's School of Physics in the heart of Sydney. We are a key laboratory in the Australian Research Council Centre of Excellence for Future Low Energy Electronics Technologies.

Our research examines the fundamental properties of low dimensional systems realised in advanced semiconductor devices, and the development of new semiconductor and superconducting devices.



20 Aug 2018
Hong and Elizabeth's paper explaining how spin-orbit interactions in a 2D hole system can cause a 30% change in the classical Hall slope has just appeared in Physical Review Letters: "Strong Spin-Orbit Contribution to the Hall Coefficient of Two-Dimensional Hole Systems", Hong Liu, E. Marcellina, A. R. Hamilton, and Dimitrie Culcer, Phys. Rev. Lett. 121, 087701 (2018). It's been chosen as an Editor's suggestion! (Elizabeth's other paper was features in the American Physical Society's news journal Physics!)
23 Jul 2018
Welcome (back) to Ian and Olivia, who are doing "Taste of Research" projects this semester. They're getting plenty of hands-on experience in the labs and cleanrooms - lots of fun.
19 Jul 2018
Scott and Roy's beautiful work studying artificial hole atoms made of silicon quantum dots has been accepted for publication in Nature Communications. The work, part of our collaboration with Andrew Dzurak's group, shows artificial atoms made using one to 8 holes, where we can see the atomic orbitals filling up according to Hund's rules, and even determine the spin states - really cool. "Spin filling and orbital structure of the first six holes in a silicon metal-oxide-semiconductor quantum dot", S. D. Liles, R. Li, C. H. Yang, F. E. Hudson, M. Veldhorst, A. S. Dzurak, A. R. Hamilton, https://arxiv.org/abs/1801.04494.
28 Jun 2018
Another paper accepted for Physical Review Letters: "Multiband Mechanism for the Sign Reversal of Coulomb Drag Observed in Double Bilayer Graphene Heterostructures" by M. Zarenia, A.R. Hamilton, F.M. Peeters, and D. Neilson is a theory paper with our colleagues explaining the unexpected experimental observations of negative Coulomb drag reported by two separate research groups in Colombia and University of Texas (Austin). A preprint is available here: https://arxiv.org/abs/1806.10732
27 Jun 2018
Feixiang's paper, studying how the van der Waals crystal Tungsten Ditelluride changes its electronic structure from a 3D Weyl semimetal as it is mane into nanometer thick flakes, has been accepted for Physical Review B: "Thickness dependent electronic structure in WTe2 thin films", Fei-Xiang Xiang, Ashwin Srinivasan, Oleh Klochan, Shi-Xue Dou, Alex R. Hamilton, and Xiao-Lin Wang. A preprint is available here: https://arxiv.org/abs/1703.02741
22 Jun 2018
Elizabeth and Ashwin's paper reporting "Electrical control of the Zeeman spin splitting in two-dimensional hole systems" has been accepted for publication in Physical Review Letters! Well done all!
"Electrical control of the Zeeman spin splitting in two-dimensional hole systems", Elizabeth Marcellina, Ashwin Srinivasan, Dmitry Miserev, Andrew Croxall, David Ritchie, Ian Farrer, Oleg Sushkov, Dimitrie Culcer, Alex Hamilton. A preprint is available here: https://arxiv.org/abs/1806.10817
1 May 2018
Cheng Tan from Lan Wang's group at RMIT is visiting us to perform magnetoresistance measurements of 2D van-der Waals heterostructure devices.
17 Apr 2018
Congratulations to Ian Thorvaldson on winning the Physics Staff Prize for Physics I.
10 Apr 2018
Daisy has been invited to the 4th Silk Road International Symposium for Distinguished Young Scholars to be held at Xi'an Jiaotong University (XJTU) from April 11-15, 2018
12 Mar 2018
Welcome to new Honours student Isaac Vorreiter.
5 Mar 2018
Matt and Alex are giving talks at the 2018 APS March meeting of the American Physical Society in Los Angeles.
28 Feb 2018
Daisy is off to Japan, to make some new samples at Tohuku university.
30 Jan 2018
Daisy is presenting an invited talk at the 2018 International Conference on Nanoscience and Nanotechnology in Wollongong. Feixiang, Matt and Scott are each giving oral talks as well.
24 Jan 2018
Congratulations to our collaborators Golrokh Akhgar, Daniel Creedon and all the team on the diamond project, whose experiments measuring the spin splitting and interface roughness for two-dimensional holes in surface conducting diamond have just appeared in Applied Physics Letters, and been selected as the cover article:
g-factor and well width variations for the two-dimensional hole gas in surface conducting diamond, G. Akhgar, D.L. Creedon, L.H. Willems van Beveren, A. Stacey, D.I. Hoxley, J.C. McCallum, L. Ley, A.R. Hamilton, and C.I. Pakes, Appl. Phys. Lett. 112, 042102 (2018); https://doi.org/10.1063/1.5010800
8 Jan 2018
Karina, Matt and Feixiang have been in Canberra at the 2018 Summer School on Topological Matter.
16 November 2017
Congratulations to Dr. Elizabeth Marcellina !
30 October 2017
The 2017 Gordon Godfrey Workshop on Spins and Strong Correlations will be held at UNSW from Monday 30th October – Friday 3rd November, with an impressive line-up of leading national and international speakers.
The workshop is FREE, and we are particularly encouraging Honours students, Masters/PhD, postdocs and ECRs to attend. There will also be an evening poster session for which we are encouraging submissions. We look forward to seeing you there.
27 September 2017
Some of UNSW's first year science students have been having fun measuring the Quantum Hall Effect in the QED group research labs under the watchful supervision of Karina Hudson, a PhD student in the QED group. The students used a helium-3 refrigerator to cool ultra-high quality gallium arsenide semiconductor chips to -273.4°C (0.25 degrees above absolute zero), and a superconducting magnet to study the Hall effect. The chips contain a thin (two-dimensional) sheet of highly mobile electrons, and at these low temperatures the students confirmed that the Hall resistance develops flat plateaus, where the Hall resistance depends only on the electron charge and Planck's constant, while the resistivity drops to zero. The unexpected discovery of the quantum Hall effect resulted in the 1985 Nobel Prize in Physics (and the fractional quantum Hall effect resulted in the 1998 Nobel Prize in Physics).
22 August 2017
Welcome to new group member Jonathan Ashlea-Alava, who joins us from Spain to start his PhD.
14 August 2017
Congratulations to Dima and Ashwin, whose combined theory and experimental paper resolving a 10-year old mystery has just been accepted into Physical Review Letters.
More than a decade ago QED researchers showed that the Zeeman splitting of holes in 1D wires was much larger if the magnetic field is applied along the wire than perpendicular to it, and this result was later confirmed by several other experimental groups. The anisotropic Zeeman splitting is a manifestation of the spin-orbit interaction, however, the mechanism of the effect has remained unclear in spite of a decade of intensive experimental and theoretical work. In the new work Dima Miserev and Oleg Sushkov show that this anisotropy is due to a new contribution to the Zeeman spin splitting that has previously been overlooked. A preprint is available here:
Mechanisms for strong anisotropy of in-plane g-factors in hole based quantum point contacts, D. S. Miserev, A. Srinivasan, I. Farrer, D. A. Ritchie, A. R. Hamilton, and O. P. Sushkov, https://arxiv.org/abs/1612.00572.
20 July 2017
Welcome to new QED group member Frederico Martins, who joins us from the Niels Bohr Institute in Copenhagen.

Topic revision: r86 - 29 Aug 2018, AlexHamilton