NEWS & EVENTS Event Calendars Event

Time & Date

14:00-15:30

Venue

Room 211, Building 4, Yunqi Campus, Zoom Meeting

Host

Dr. Changxi Zheng, PI of School of Science, Westlake University

Audience

Faculty and Staff,Graduate Students,Undergraduate Students

Category

Academics and Research

Physics Colloquium | Bent Weber: Proximity-Induced Superconductivity in Epitaxial Quantum Spin Hall Heterostructures

Time: 14:00-15:30, Tuesday, Feb. 23rd, 2021

Host: Dr. Changxi Zheng, PI of School of Science, Westlake University

Venue: Room 211, Building 4, Yunqi Campus, Zoom Meeting

Online: Zoom Meeting (Meeting ID: 857 070 9222)


Speaker

Prof. Bent Weber

Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University

Biography:

Bent Weber is Singapore National Research Foundation (NRF) Fellow and Nanyang Assistant Professor (NAP) of Physics at Nanyang Technological University (NTU) Singapore. Weber obtained his PhD from the Centre for Quantum Computation and Communication Technology (CQC2T) at The University of New South Wales (UNSW), where he developed atomic-scale silicon quantum devices by scanning tunnelling microscopy. His work on donor-based spin qubits was published in a range of high-impact papers, including Science, Nature Nanotechnology, Nano Letters, npj Quantum Information, and Physical Review Letters. Weber has held an Australian Research Council (ARC) DECRA fellowship at Monash University, Australia, and is an Associate Investigator of the ARC Centre of Excellence in Future Low Energy Electronics Technologies (FLEET). Weber’s group at NTU employs complementary local probe and transport spectroscopy to investigate 2D and topological materials for their potential in quantum device applications.


Abstract:

The interplay of topology and superconductivity in condensed matter has become a subject of intense research for its importance in realizing and advancing approaches to Majorana based topological quantum computing. Atomically thin (2D) topological materials – such as the quantum spin Hall (QSH) insulator – promise large intrinsic band gaps, that are robust to disorder and can carry topological superconductivity without the necessity to apply external magnetic fields. Yet, reports of superconductivity in atomically thin QSH systems are sparse, given the significant challenge to achieve stability and uniformity via high-quality crystalline and atomically abrupt interfaces. Here we show that both can be achieved in epitaxially grown van-der-Waals heterostructures of the quantum spin Hall insulator 1T’-WTe2and the layered van-der-Waals superconductor 2H-NbSe2.

We report stable proximity-induced superconductivity with pairing amplitude as large as 0.6 meV, resolved by scanning tunnelling spectroscopy at 500mK. We describe both the intrinsic superconductivity of the substrate, and that induced in WTe2, within a self-consistent framework of multiband superconductivity, allowing us to untangle their respective contributions to the superconducting density of states. Comparison with mean-field theoretical models confirms the magnitude of the induced pairing amplitude in both WTe2QSH bulk and edge – a result of a strong hybridization of electronic state with the substrate. The realization of a superconducting quantum spin Hall platform may have implications for QSH based topological quantum computation.


Contact:

School of Science, Ms. Zhong, zhongmengzhen@westlake.edu.cn


Time & Date

14:00-15:30

Venue

Room 211, Building 4, Yunqi Campus, Zoom Meeting

Host

Dr. Changxi Zheng, PI of School of Science, Westlake University

Audience

Faculty and Staff,Graduate Students,Undergraduate Students

Category

Academics and Research