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Title: Bulk‐Rashba Effect with Suppressed Spin Relaxation in a Polar Phase of Bi 1‐ x In 1+ x O 3
Abstract The Rashba effect enables control over the spin degree of freedom, particularly in polar materials where the polar symmetry couples to Rashba‐type spin splitting. The exploration of this effect, however, has been hindered by the scarcity of polar materials exhibiting the bulk‐Rashba effect and rapid spin‐relaxation effects dictated by the D'yakonov–Perel mechanism. Here, a polar LiNbO3‐typeR3cphase of Bi1‐xIn1+xO3withx≈0.15–0.24 is stabilized via epitaxial growth, which exhibits a bulk‐Rashba effect with suppressed spin relaxation as a result of its unidirectional spin texture. As compared to the previously observed non‐polarPnmaphase, this polar phase exhibits higher conductivity, reduced bandgap, and enhanced dielectric and piezoelectric responses. Combining first‐principles calculations and multimodal magnetotransport measurements, which reveal weak (anti)localization, anisotropic magnetoresistance, planar‐Hall effect, and nonreciprocal charge transport, a bulk‐Rashba effect without rapid spin relaxation is demonstrated. These findings offer insights into spin‐orbit coupling physics within polar oxides and suggest potential spintronic applications.  more » « less
Award ID(s):
2102895 2329111 2104397
PAR ID:
10618417
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; « less
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Materials
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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