Global phase diagram and quantum spin liquids in a spin $\frac{1}{2}$ triangular antiferromagnet
Abstract
For this research, we study the spin1/2 Heisenberg model on the triangular lattice with the nearestneighbor J _{1} > 0 , the nextnearestneighobr J _{2} > 0 Heisenberg interactions, and the additional scalar chiral interaction Jχ ($$\vec{S}$$ _{i} × $$\vec{S}$$ _{j} ) · $$\vec{S}$$ _{k} for the three spins in all the triangles using largescale density matrix renormalization group calculation on cylinder geometry. With increasing J _{2} (J _{2} / J _{1} ≤ 0.3 ) and Jχ (Jχ / J _{1} ≤ 1.0 ) interactions, we establish a quantum phase diagram with the magnetically ordered 120°, stripe, and noncoplanar tetrahedral phase. In between these magnetic order phases, we find a chiral spin liquid (CSL) phase, which is identified as a ν = 1/2 bosonic fractional quantum Hall state with possible spontaneous rotational symmetry breaking. By switching on the chiral interaction, we find that the previously identified spin liquid in the J _{1}  J _{2} triangular model (0.08 ≲ J _{2} / J _{1} ≲ 0.15) shows a phase transition to the CSL phase at very small Jχ. We also compute the spin triplet gap in both spin liquid phases, and our finitesize results suggest a large gap in the odd topological sector but a small or vanishing gap in the even sector. Lastly, we discuss the implications of our results on the nature of the spin liquid phases.
 Authors:
 Florida State Univ., Tallahassee, FL (United States)
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 California State University, Northridge, CA (United States)
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC22)
 OSTI Identifier:
 1414112
 Alternate Identifier(s):
 OSTI ID: 1374653
 Report Number(s):
 LAUR1723332
Journal ID: ISSN 24699950; PRBMDO
 Grant/Contract Number:
 AC5206NA25396
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review B
 Additional Journal Information:
 Journal Volume: 96; Journal Issue: 7; Journal ID: ISSN 24699950
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE
Citation Formats
Gong, ShouShu, Zhu, Wei, Zhu, Jianxin, Sheng, Donna N., and Yang, Kun. Global phase diagram and quantum spin liquids in a spin 12 triangular antiferromagnet. United States: N. p., 2017.
Web. doi:10.1103/PhysRevB.96.075116.
Gong, ShouShu, Zhu, Wei, Zhu, Jianxin, Sheng, Donna N., & Yang, Kun. Global phase diagram and quantum spin liquids in a spin 12 triangular antiferromagnet. United States. doi:10.1103/PhysRevB.96.075116.
Gong, ShouShu, Zhu, Wei, Zhu, Jianxin, Sheng, Donna N., and Yang, Kun. 2017.
"Global phase diagram and quantum spin liquids in a spin 12 triangular antiferromagnet". United States.
doi:10.1103/PhysRevB.96.075116.
@article{osti_1414112,
title = {Global phase diagram and quantum spin liquids in a spin 12 triangular antiferromagnet},
author = {Gong, ShouShu and Zhu, Wei and Zhu, Jianxin and Sheng, Donna N. and Yang, Kun},
abstractNote = {For this research, we study the spin1/2 Heisenberg model on the triangular lattice with the nearestneighbor J1 > 0 , the nextnearestneighobr J2 > 0 Heisenberg interactions, and the additional scalar chiral interaction Jχ ($\vec{S}$i × $\vec{S}$j ) · $\vec{S}$k for the three spins in all the triangles using largescale density matrix renormalization group calculation on cylinder geometry. With increasing J2 (J2 / J1 ≤ 0.3 ) and Jχ (Jχ / J1 ≤ 1.0 ) interactions, we establish a quantum phase diagram with the magnetically ordered 120°, stripe, and noncoplanar tetrahedral phase. In between these magnetic order phases, we find a chiral spin liquid (CSL) phase, which is identified as a ν = 1/2 bosonic fractional quantum Hall state with possible spontaneous rotational symmetry breaking. By switching on the chiral interaction, we find that the previously identified spin liquid in the J1  J2 triangular model (0.08 ≲ J2 / J1 ≲ 0.15) shows a phase transition to the CSL phase at very small Jχ. We also compute the spin triplet gap in both spin liquid phases, and our finitesize results suggest a large gap in the odd topological sector but a small or vanishing gap in the even sector. Lastly, we discuss the implications of our results on the nature of the spin liquid phases.},
doi = {10.1103/PhysRevB.96.075116},
journal = {Physical Review B},
number = 7,
volume = 96,
place = {United States},
year = 2017,
month = 8
}
Web of Science

Magnetic phase diagram and multiferroicity of ${\mathrm{Ba}}_{3}{\mathrm{MnNb}}_{2}{\mathrm{O}}_{9}$ : A spin  $\frac{5}{2}$ triangular lattice antiferromagnet with weak easyaxis anisotropy
Here we have performed magnetic, electric, thermal and neutron powder diffraction (NPD) experiments as well as density functional theory (DFT) calculations on Ba _{3}MnNb _{2} O _{9}. All results suggest that Ba _{3}MnNb _{2} O _{9} is a spin5/2 triangular lattice antiferromagnet (TLAF) with weak easyaxis anisotropy. At zero field, we observed a narrow twostep transition at T _{N1} = 3.4 K and T _{N2} = 3.0 K. The neutron diffraction measurement and the DFT calculation indicate a 120 spin structure in ab plane with outofplane canting at low temperatures. With increasing magnetic field, the 120 spin structure evolves intomore »Cited by 17