CNS Seminar: "Probing Topological Superconductivity in HgTe/HgCdTe Quantum Wells," Hechen Ren, Yacoby Group, HU

April 28, 2017

Friday, April 28th, LISE 303, 12PM


Abstract: Decoherence due to local noise is the worst enemy of quantum information. To combat this, topological quantum computing has been proposed as a powerful and elegant scheme to encode quantum information globally, and hence stay robust against local perturbations. In the past five years, this field has begun to see experimental breakthroughs made possible by combining superconductivity and various low-dimensional quantum materials with significant spin-orbit interaction. Here in the Yacoby group, we fabricate superconducting devices such as Josephson junctions and DC SQUIDs with high quality HgTe/HgCdTe quantum wells, which is the first discovered quantum spin Hall insulator. In this talk, I will present results on induced superconductivity both related to the quantum spin Hall effect and to the controlled finite momentum pairing in the bulk. I will also explain how both results connect directly to Majorana bound states – the most prominent candidate for realizing topologically protected qubits so far. With that, I will discuss our current efforts to probe tunneling spectroscopy of the induced superconducting states.

About the Speaker: Hechen Ren is a Ph.D. candidate in the Yacoby group at Harvard University. She received a Bachelor of Arts from Columbia University in physics and mathematics. While at Columbia, she worked with Dr. Philip Kim and her research was on developing layered graphene and hBN devices and studying quantum Hall effects in them. Hechen joined the Yacoby group in 2011 and has collaborated with members both in and outside the Harvard physics community. Currently, she works on innovating tunnel probe devices on hybrid superconductor – quantum well structures and measuring spectroscopy of topological superconductivity. She has authored and co-authored several Nature Physics papers.