Weak Mott insulators on the triangular lattice: Possibility of a gapless nematic quantum spin liquid

2009/07/31 by Tarun Grover, Nandini Trivedi, N. Trivedi +2 · 100 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Condensed matter physics #Ferromagnetism #Gapless playback #Heisenberg model #Hexagonal lattice #Hubbard model #Lattice (music) #Liquid crystal #Monte Carlo method #Mott insulator #Organic and Molecular Conductors Research #Physics #Physics of Superconductivity and Magnetism #Quantum Monte Carlo #Quantum mechanics #Quantum spin liquid #Spin polarization #Superconductivity #Variational Monte Carlo #cond-mat.str-el #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevb.81.245121

published in Physical Review B 81(24) (American Physical Society) · Longer version, 7+ pages, 5 figures

openalex publication_date 2010/06/18 · arxiv created 2010/12/29 · arxiv updated 2011/01/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We study the energetics of Gutzwiller projected BCS states of various symmetries for the triangular lattice antiferromagnet with a four-particle ring exchange using variational Monte Carlo methods. In a range of parameters the energetically favored state is found to be a projected d_x²\ensuremath-y² paired state which breaks lattice rotational symmetry. We show that the properties of this nematic or orientationally ordered paired spin-liquid state as a function of temperature and pressure can account for many of the experiments on organic materials. We also study the ring-exchange model with ferromagnetic Heisenberg exchange and find that among the studied ans"atze, a projected f-wave state is the most favorable.

Citations

• Orbital magnetic field effects in spin liquid with spinon Fermi sea: Possible application toκ−(ET)2Cu2(CN)3
• From Néel long-range order to spin liquids in the multiple-spin exchange model
• Theory of a continuous Mott transition in two dimensions
• Mott Transition from a Spin Liquid to a Fermi Liquid in the Spin-Frustrated Organic Conductorκ−(ET)2Cu2(CN)3
• Amperean Pairing Instability in the U(1) Spin Liquid State with Fermi Surface and Application toκ−(BEDT−TTF)2Cu2(CN)3
• Spin-liquid and magnetic phases in the anisotropic triangular lattice: The case ofκ−(ET)2X
• U(1) Gauge Theory of the Hubbard Model: Spin Liquid States and Possible Application toκ−(BEDT−TTF)2Cu2(CN)3
• Equivalence of the resonating-valence-bond and fractional quantum Hall states
• Spin Liquid State in an Organic Mott Insulator with a Triangular Lattice
• Physics of projected wavefunctions
• Chiral spin states and superconductivity
• Fractionalization in the Cuprates: Detecting the Topological Order