TY - JOUR
T1 - Competing magnetic interactions in a spin- 12 square lattice
T2 - Hidden order in Sr2VO4
AU - Kim, Bongjae
AU - Khmelevskyi, Sergii
AU - Mohn, Peter
AU - Franchini, Cesare
N1 - Publisher Copyright:
© 2017 American Physical Society.
PY - 2017/11/8
Y1 - 2017/11/8
N2 - With decreasing temperature, Sr2VO4 undergoes two structural phase transitions, tetragonal-to-orthorhombic-to-tetragonal, without long-range magnetic order. Recent experiments suggest that only at very low temperature, Sr2VO4 might enter a yet-unknown phase with long-range magnetic order, but without orthorhombic distortion. By combining relativistic density functional theory with an extended spin-1/2 compass-Heisenberg model, we find an antiferromagnetic single-stripe ground state with highly competing exchange interactions, involving a non-negligible interlayer coupling, which places the system at the crossover between the XY-model and Heisenberg-model regimes. Most strikingly, we find a strong two-site "spin-compass" exchange anisotropy which is relieved by the orthorhombic distortion induced by the spin stripe order. Based on these results, we discuss the origin of the hidden-order phase and the possible formation of a spin liquid at low temperatures.
AB - With decreasing temperature, Sr2VO4 undergoes two structural phase transitions, tetragonal-to-orthorhombic-to-tetragonal, without long-range magnetic order. Recent experiments suggest that only at very low temperature, Sr2VO4 might enter a yet-unknown phase with long-range magnetic order, but without orthorhombic distortion. By combining relativistic density functional theory with an extended spin-1/2 compass-Heisenberg model, we find an antiferromagnetic single-stripe ground state with highly competing exchange interactions, involving a non-negligible interlayer coupling, which places the system at the crossover between the XY-model and Heisenberg-model regimes. Most strikingly, we find a strong two-site "spin-compass" exchange anisotropy which is relieved by the orthorhombic distortion induced by the spin stripe order. Based on these results, we discuss the origin of the hidden-order phase and the possible formation of a spin liquid at low temperatures.
UR - http://www.scopus.com/inward/record.url?scp=85038864877&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.96.180405
DO - 10.1103/PhysRevB.96.180405
M3 - Article
AN - SCOPUS:85038864877
SN - 2469-9950
VL - 96
JO - Physical Review B
JF - Physical Review B
IS - 18
M1 - 180405
ER -