Ambipolar gate effect and low temperature magnetoresistance of ultrathin La0.8Ca0.2MnO3 films.
Ultrathin La(0.8)Ca(0.2)MnO(3) films have been measured in a field-effect geometry. The gate electric field produces a significant ambipolar decrease in resistance at low temperatures. This is attributed to the development of a pseudogap in the density of states and the coupling of localized charge to strain. Within a mixed phase scenario, the gate effect and magnetoresistance are interpreted in the framework of a "general susceptibility," which describes how phase boundaries move through a hierarchical pinning landscape.
Eblen-Zayas
M
M
School of Physics and Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, Minnesota 55455, USA.
Bhattacharya
A
A
Staley
N E
NE
Kobrinskii
A L
AL
Goldman
A M
AM