Benjamin Gray
(Photo: Submitted)
A University of Arkansas doctoral student was awarded the
Wayne B. Nottingham Prize for the best student paper presented at the 73rd
annual Physical Electronics Conference.
Benjamin A. Gray, who has been working on the project as
part of his dissertation performed in the Laboratory for Artificial Quantum
Matter of Physics in the J. William Fulbright College of Arts and Sciences,
received $1,000 and a certificate at the conference held in Raleigh, N.C., June
18-21.
Gray is the first University of Arkansas student to win the prestigious
Nottingham Prize. Previous winners have come from institutions such as Boston
University, the Max Planck Institute for Solid State Physics, Cornell
University, the Massachusetts Institute of Technology,
Northwestern University and Harvard University. Past winners also include
members of the National Academy of Sciences.
The Nottingham Prize was established from contributions
given in memory of Professor Wayne B. Nottingham of the Massachusetts Institute of Technology by
his many friends and associates. The conference focuses on new research results
in surface science and in the chemistry of
surfaces and interfaces.
Gray’s paper, titled “Interfacial controlled carrier doping
of a high-temperature superconductor,” and directed by his adviser, physics
Professor Jak Chakhalian, was co-authored by fellow doctoral student Derek
Meyers; U of A research associates Yanwei Cao, Michael Kareev and Srimanta
Middey.
The research team experimented with new methods for
releasing the rich properties of complex oxide materials, Gray said.
“These are the most enigmatic class of materials,” Gray
said. “According to fundamental quantum physics models, most oxide materials
should be excellent conductors of heat and electricity but surprisingly,
experiments find that they are the strongest insulators. In these materials,
electrons strongly interact with each other, which essentially freeze them in
place.
“Over the last few decades, researchers have discovered
techniques to remove parts of these interactions and free the electrons to move
through those crystals,” he said. “Once unlocked, these systems display
diverse, often exotic and technologically important phenomena.”
The research team used a newly developed crystal growth
technique to create alternating layers, consisting of a high-temperature
superconductor and ferromagnetic oxide with individual layers’ thicknesses of
only a few atomic planes, Gray said.
“The unique configuration of atoms at the interface between
the layers establishes movement of electrons across the interface that switches
the high-temperature superconductor between the superconducting and insulating
states,” he said. “Our finding will hopefully pave the way to novel quantum states
through interfacial engineering.”