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arXiv · 2209.03672

Observation of strange metal in hole-doped valley-spin insulator

Tuan Dung Nguyen·Baithi Mallesh·Seon Je Kim·Houcine Bouzid·Byeongwook Cho·Xuan Phu Le·Tien Dat Ngo·Won Jong Yoo·Young-Min Kim·Dinh Loc Duong·Young Hee Lee
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Abstract

Temperature-linear resistance at low temperatures in strange metals is an exotic characteristic of strong correlation systems, as observed in high-TC superconducting cuprates, heavy fermions, Fe-based superconductors, ruthenates, and twisted bilayer graphene. Here, we introduce a hole-doped valley-spin insulator, V-doped WSe2, with hole pockets in the valence band. The strange metal characteristic was observed in VxW1-xSe2 at a critical carrier concentration of 9.5 x 10^20 cm-3 from 150 K to 1.8 K. The unsaturated magnetoresistance is almost linearly proportional to the magnetic field. Using the ansatz R(H,T) - R(0,0) ~ [(alpha.k.T)^2+(gamma.mu.B)^2]^1/2, the gamma/alpha ratio is estimated approximately to 4, distinct from that for the quasiparticles of LSCO, BaFe2(As1-xPx)2 (gamma/alpha=1) and bosons of YBCO (gamma/alpha=2). Our observation opens up the possible routes that induce strong correlation and superconductivity in two-dimensional materials with strong spin-orbit coupling.

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Tuan Dung Nguyen, Baithi Mallesh, Seon Je Kim, Houcine Bouzid, Byeongwook Cho, Xuan Phu Le, Tien Dat Ngo, Won Jong Yoo, Young-Min Kim, Dinh Loc Duong, Young Hee Lee. 2022-09-08. Observation of strange metal in hole-doped valley-spin insulator. https://arxiv.org/abs/2209.03672

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