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Title: Carrier density control of magnetism and Berry phases in doped EuTiO3
In materials with broken time-reversal symmetry, the Berry curvature acts as a recip- rocal space magnetic field on the conduction electrons and is a significant contribution to the magnetotransport properties, including the intrinsic anomalous Hall effect. Here, we report neutron diffraction, transport, and magnetization measurements of thin films of doped EuTiO3, an itinerant magnetic material, as a function of carrier density and magnetic field. These films are itinerant antiferromagnets at all doping concentrations. At low carrier densities, the magnetoresistance indicates a metamag- netic transition, which is absent at high carrier densities (>6 × 1020 cm-3). Strikingly, the crossover coincides with a sign change in the spontaneous Hall effects, indicating a sign change in the Berry curvature. We discuss the results in the context of the band structure topology and its coupling to the magnetic texture.  more » « less
Award ID(s):
1652994
NSF-PAR ID:
10084126
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
APL materials
Volume:
6
Issue:
056105
ISSN:
2166-532X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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