Energy-gap driven low-temperature magnetic and transport properties in Cr1/3MS2(M = Nb, Ta)

Hicken, T.J.; Hawkhead, Z.; Wilson, M.N.; Huddart, B.M.; Hall, A.E.; Balakrishnan, G.; Wang, C.; Pratt, F.L.; Clark, S.J.; Lancaster, T.

Abstract

The helimagnets Cr1/3MS2 (M = Nb or Ta) have attracted renewed attention due to the discovery of a chiral soliton lattice (CSL) stabilized in an applied magnetic field, but reports of unusual low-temperature transport and magnetic properties in this system lack a unifying explanation. Here, we present electronic structure calculations that demonstrate the materials are half metals. There is also a gaplike feature (width in range 40–100 meV) in the density of states of one spin channel. This electronic structure explains the low-temperature electronic and magnetic properties of Cr1/3MS2 (M = Nb or Ta), with the gaplike feature particularly important for explaining the magnetic behavior. Our magnetometry measurements confirm the existence of this gap. Dynamic spin fluctuations driven by excitations across this gap are seen over a wide range of frequencies (0.1 Hz to MHz) with ac susceptibility and muon-spin relaxation (μ+SR) measurements. We show further how effects due to the CSL in Cr1/3NbS2, as detected with μ+SR, dominate over the gap driven magnetism when the CSL is stabilized as the majority phase.

Citation

Hicken, T., Hawkhead, Z., Wilson, M., Huddart, B., Hall, A., Balakrishnan, G., …Lancaster, T. (2022). Energy-gap driven low-temperature magnetic and transport properties in Cr1/3MS2(M = Nb, Ta). Physical Review B, 105(6), Article L060407. https://doi.org/10.1103/physrevb.105.l060407

• Journal Article Type: Article
• Acceptance Date: Feb 8, 2022
• Online Publication Date: Feb 22, 2022
• Publication Date: Feb 1, 2022
• Deposit Date: Feb 23, 2022
• Publicly Available Date: Jun 15, 2022
• Journal: Physical Review B
• Print ISSN: 2469-9950
• Electronic ISSN: 2469-9969
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 105
• Issue: 6
• Article Number: L060407
• DOI: https://doi.org/10.1103/physrevb.105.l060407
• Public URL: https://durham-repository.worktribe.com/output/1212784
• Related Public URLs: https://arxiv.org/abs/2105.01393