TY - JOUR
T1 - Constraining the parameter space of a quantum spin liquid candidate in applied field with iterative optimization
AU - Steinhardt, William
AU - Shi, Zhenzhong
AU - Samarakoon, Anjana
AU - Dissanayake, Sachith
AU - Graf, David
AU - Liu, Yaohua
AU - Zhu, Wei
AU - Marjerrison, Casey
AU - Batista, Cristian D.
AU - Haravifard, Sara
N1 - Publisher Copyright:
© 2021 Published by the American Physical Society
PY - 2021/9
Y1 - 2021/9
N2 - The quantum spin liquid (QSL) state is an exotic state of matter featuring a high degree of entanglement and lack of long-range magnetic order in the zero-temperature limit. The triangular antiferromagnet is a candidate QSL host, and precise determination of the Hamiltonian parameters is critical to understanding the nature of the possible ground states. However, the presence of chemical disorder has made directly measuring these parameters challenging. Here we report neutron scattering and magnetic susceptibility measurements covering a broad range of applied magnetic field at low temperature. Our data shows a field-induced crossover in , which we reproduce with complementary classical Monte Carlo and density matrix renormalization group simulations. Neutron scattering data above and below the crossover reveal a shift in scattering intensity from to points and, collectively, our measurements provide essential characteristics of the phase crossover that we employ to strictly constrain proposed magnetic Hamiltonian parameters despite the chemical disorder. Constrained exchange parameters further suggest the material's proximity to the QSL state in the clean limit. More broadly, our approach demonstrates a means of pursuing QSL candidates where Hamiltonian parameters might otherwise be obscured by disorder.
AB - The quantum spin liquid (QSL) state is an exotic state of matter featuring a high degree of entanglement and lack of long-range magnetic order in the zero-temperature limit. The triangular antiferromagnet is a candidate QSL host, and precise determination of the Hamiltonian parameters is critical to understanding the nature of the possible ground states. However, the presence of chemical disorder has made directly measuring these parameters challenging. Here we report neutron scattering and magnetic susceptibility measurements covering a broad range of applied magnetic field at low temperature. Our data shows a field-induced crossover in , which we reproduce with complementary classical Monte Carlo and density matrix renormalization group simulations. Neutron scattering data above and below the crossover reveal a shift in scattering intensity from to points and, collectively, our measurements provide essential characteristics of the phase crossover that we employ to strictly constrain proposed magnetic Hamiltonian parameters despite the chemical disorder. Constrained exchange parameters further suggest the material's proximity to the QSL state in the clean limit. More broadly, our approach demonstrates a means of pursuing QSL candidates where Hamiltonian parameters might otherwise be obscured by disorder.
UR - http://www.scopus.com/inward/record.url?scp=85112733749&partnerID=8YFLogxK
U2 - 10.1103/PhysRevResearch.3.033050
DO - 10.1103/PhysRevResearch.3.033050
M3 - Article
AN - SCOPUS:85112733749
SN - 2643-1564
VL - 3
JO - Physical Review Research
JF - Physical Review Research
IS - 3
M1 - 033050
ER -