Giant Transverse Transport Effects In Topological Quantum Magnets

2022-08-17 Prof. Prasanta Kumar Muduli, IIT Madras

ABSTRACT :

Topological quantum magnets are materials whose properties are determined by the coupling between magnetism and nontrivial band topology. These materials carry dissipationless surface and edge currents which are promising for quantum information and spintronic applications with low dissipation. Topological quantum magnets show giant transverse transport effects caused by the Berry curvature arising from the nontrivial topology of the electronic band structure in the momentum space. In some cases, nonvanishing real space Berry curvature can emerge in these quantum magnets due to non-collinear magnetic configuration which often has a nonzero scalar spin chirality. Recently discovered topological quantum magnets such as Dirac and Weyl semimetals host relativistic fermio ns which enable observation of high energy physics phenomena such as the chiral anomaly and mixed axial–gravitational anomaly in condensed matter physics. Until now only a handful of materials have been experimentally validated to be magnetic Weyl semimetals. Furthermore, most of the present study is limited to bulk samples and device applications of these materials are scarce. In this talk, I will primarily focus on recently discovered antiferromagnetic Weyl semimetal Mn3Sn. Although it is an antiferromagnet with negligible net magnetization combined effect of large Berry curvature and multipoles leads to large macroscopic transverse responses such as the anomalous Hall and Nernst effects, the magneto-optical effect, and the novel magnetic spin Hall effect. In particular, I will present our recent discovery of the magnetic spin Hall effect in Mn3Sn using nanoscale spintronic devices.

Event Name

Seminars

Place

S N Bose Hall (HSB 210)

Start Time

16:00

End Time

17:00

External Link

PDF to Talk