Seminars

Superconductivity under Extreme Conditions

by Prof. Jochen Wosnitza (Dresden High Magnetic Field Laboratory (HLD-EMFL))

Asia/Shanghai
Tsung-Dao Lee Institute/N6F-N600 - Lecture Room (Tsung-Dao Lee Institute)

Tsung-Dao Lee Institute/N6F-N600 - Lecture Room

Tsung-Dao Lee Institute

40
Description

Host: Prof. Vadim Grinenko  

Venue: TDLI Meeting Room N600

Tencent Meeting link: https://meeting.tencent.com/dm/TTXEcz9iyeLS

Meeting ID: 975232008, no password

 

Abstract:

High magnetic fields and superconductivity are usually incompatible. The magnetic field favors parallel electron spins, while superconductivity requires Cooper pairs with antiparallel spins. There exist, however, some superconductors, in which superconductivity survives to extraordinary high magnetic fields as we found in studies using static and pulsed magnetic fields up to 70 T provided at the Dresden High Magnetic Field Laboratory.

As a first example, I will present our robust evidence for the existence of the so-called Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state in quasi-two-dimensional organic superconductors. Besides specific-heat and magnetization results, NMR studies give strong microscopic evidence for the realization of the FFLO state. A one-dimensional sinusoidal order-parameter modulation can favorably explain the NMR spectra in this high-field low-temperature phase. I will further discuss the recently discovered heavy-fermion superconductor UTe2. This material shows multiple unconventional superconducting phases under field and pressure with unusually large upper critical fields. For certain field orientations, superconductivity even reappears at very high fields and survives to a record-breaking upper critical field of about 73 T. The Jaccarino-Peter effect is a likely mechanism for the appearance of this reentrant superconductivity.

Biography:

Academic education and professional Career:

2004-Now

Professorship at University of Technology Dresden (TUD) and director of the 

Hochfeld-Magnetlabor Dresden (HLD) at the HZDR

2001-2004

Professorship for “Low-Temperature Physics” at the University of Technology 

Dresden (TUD), Germany

1995

Habilitation in Experimental Physics at Universität Karlsruhe (TH), Germany

1990-1991

Postdoc at Argonne National Laboratory, Argonne, Illinois, USA

1988

PhD, Universität Karlsruhe (TH), Germany

1985

Diploma (Physics) at RWTH Aachen, Germany

Selected other (Academic) Positions:

2023-Now

Member of the Scientific Advisory Board of the Center for Electronic Correlations 

and Magnetism (EKM), Augsburg University

2015-2021

Member of the selection committee for the Heinz Maier-Leibnitz prize

2011- Now

Outstanding Referee for the journals of the American Physical Society

2008- Now

Head of the Scientific and Technical Council (Wissenschaftlich-Technischer Rat) of 

the Helmholtz-Zentrum Dresden-Rossendorf

2007-2015

Advisory Professorship at the Huazhong University of Science and Technology, 

Wuhan, China

2004-2012

Member of the DFG (Deutsche Forschungsgemeinschaft) review board; 2010 -

2012 chair of the review board “Physics of Condensed Matter”

2003-2005

Dean of student affairs of the physics department at the TU Dresden

1999-2001

Lecturer at Universität Karlsruhe (TH), Germany

1986-1999

Research Associate and Scientific Assistant, Universität Karlsruhe (TH), Germany

1985-1986

Research Associate at RWTH Aachen