Monash Engineering/FLEET seminar. Old and new approaches for designing and detecting topological signatures in quantum wires

Dr Karina Hudson, Postdoctoral Research Fellow, Sydney Quantum Academy, Associate Investigator, FLEET, UNSW Sydney

In-person at Monash University (Clayton), New Horizons Building, room G30

or live via zoom

Or go to https://monash.zoom.us/join and enter Meeting ID: 883 9267 8961 and Passcode: 1234

In recent years, enthusiasm has grown for quantum hardware that can host topological states, useful for dissipationless electronics and robust quantum computing as well as more fundamental physics. Quantum wires with spin-orbit and superconductivity that could host bound Majorana zero modes and p-wave superconductivity are an attractive platform to study as the quantum states are easily manipulated with gate voltages, similar to ordinary transistors. However, in the last couple of years two papers reporting signatures of Majorana zero modes have been retracted, and expressions of concern registered for another two publications. Much of the controversy appears to have arisen due to our incomplete understanding of conductance in quantum wires, as disorder and non-adiabatic transmission can mimic and mask topological signatures.

In this talk I will explain the pitfalls that have led to confusion and controversy around topological signatures in 1D quantum wires. I will also cover the internode collaboration within FLEET along with theory collaborators at the University of Wisconsin-Madison that has made progress towards a new approach of intelligent design of quantum wires with controllable spin-orbit interaction that may open a new pathway to engineering topological states.

Karina is an FLEET Associate Investigator, a Postdoctoral Fellow of the Sydney Quantum Academy and a member of Alex Hamilton’s Quantum Electronic Devices group at UNSW Sydney. Her main research interest is spin orbit interaction and topological states in 1D quantum wires.