Crossover from positive to negative magnetoresistance in a spinel.
We present a new class of colossal magnetoresistance materials based on a series of frustrated spinels. The spin glass-like compound Zn0.95Cu0.05Cr2Se4, shows a field-induced transition to a ferromagnetic, which is associated with a highly unusual negative magnetoresistance effect (MR > 80%) in low magnetic field. At higher temperatures there is an unprecedented crossover to positive magnetoresistance (MR > 50%).
Parker
Dinah R
DR
The Royal Institution of Great Britain, and Department of Chemistry, University College London, UK.
Green
Mark A
MA
Bramwell
Steven T
ST
Wills
Andrew S
AS
Gardner
Jason S
JS
Neumann
Dan A
DA