"Colloquium Lecture: Probing the physics of complex oxide interfaces with scanning SQUID microscopy"

Date: 
Mon, 13/04/201512:00-13:30
Location: 
Levin building, Lecture Hall No. 8
Lecturer: Dr. Beena Kalisky
Affiliation: Department of Physics,
Bar-Ilan University
Abstract:
Complex oxide materials have a broad range
of functionality such as ferromagnetism,
piezoelectricity, and superconductivity. When
combinations of complex oxides are grown as
heterostructures, changes in the local
electronic-structure at the interface can
create new electronic phases that cannot exist
in either parent material. One example is the
interface formed by growing LAO on STO.
Though both materials are non magnetic
insulators, the interface between them shows
conductivity, superconductivity and even
magnetism.
In the LAO/STO system we found nanoscale
patches of magnetism coexisting with
superconductivity. I will describe our efforts
to understand this magnetism, by mapping
the landscape of ferromagnetism,
superconductivity and conductivity with
scanning SUQID microscopy. I will focus on
viewing the local distribution of current flow
at the interface, where we found that the
current flow is enhanced on conductive
channels that are related to STO tetragonal
domain structure. The interplay between
substrate domains and the interface provides
an additional mechanism for understanding
and controlling the behaviors of
heterostructures.