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Title: Singular angular magnetoresistance in a magnetic nodal semimetal
Transport coefficients of correlated electron systems are often useful for mapping hidden phases with distinct symmetries. Here we report a transport signature of spontaneous symmetry breaking in the magnetic Weyl semimetal cerium-aluminum-germanium (CeAlGe) system in the form of singular angular magnetoresistance (SAMR). This angular response exceeding 1000% per radian is confined along the high-symmetry axes with a full width at half maximum reaching less than 1° and is tunable via isoelectronic partial substitution of silicon for germanium. The SAMR phenomena is explained theoretically as a consequence of controllable high-resistance domain walls, arising from the breaking of magnetic point group symmetry strongly coupled to a nearly nodal electronic structure. This study indicates ingredients for engineering magnetic materials with high angular sensitivity by lattice and site symmetries.
Authors:
; ; ; ; ;
Award ID(s):
1818533
Publication Date:
NSF-PAR ID:
10158638
Journal Name:
Science
Volume:
365
Issue:
6451
Page Range or eLocation-ID:
377 to 381
ISSN:
0036-8075
Sponsoring Org:
National Science Foundation
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