School of Physical and Chemical Sciences Seminar Series

Superconducting Sandwiches

Speaker

Dr Ben Mallett

Institute

Research Fellow, University of Auckland

Time & Place

Fri, 25 Aug 2017 11:00:00 NZST in Room 531, Level 5, Rutherford Building

All are welcome

Abstract

When we sandwiched a high-temperature superconductor between two layers of a specific manganite last year, we discovered that the superconductor adopts a startling new ground state. Manganites are known for their colossal magneto resistance (where the resistance drops by orders of magnitude in a magnetic field), and the high-temperature superconductors are known for, well, superconductivity (still unexplained phenomenon in these systems). Our ‘superconductor sandwich’ of these two materials exhibits many unusual new effects not seen in either material; e.g. it's an exotic granular-superconductor in zero magnetic-field, then it becomes a customary superconductor in high-field or high-current (both of which normally destroy the superconducting state). The chief suspect in causing this new ground state is the manganite - a material with its own interesting arsenal of charge- and spin- ordered states. The question is, how do the two materials couple together to cause these unusual effects?