Dynamical spin structure factors of quantum spin nematic states

Abstract

Dynamical spin structure factors of quantum spin nematic states are calculated in a spin-1/2 square-lattice J1-J2 model with ferromagnetic J1 and competing antiferromagnetic J2 interactions. To this end, we use a fermion representation, generalizing it to N flavors. We begin with a spin-triplet pairing state of fermion fields, called Z2 planar state, which is a stable saddle-point solution in the large-N limit in a finite parameter range where the couplings J1 and J2 compete strongly [R. Shindou and T. Momoi, Phys. Rev. B 80, 064410 (2009)]. Using a large-N expansion, we take into account fluctuations around this saddle point up to corrections of order 1/N. The dynamical spin structure factors thus obtained signify the existence of gapless q-linear director-wave (spin-wave) modes at q=(0,0) and gapped `gauge-field' like collective modes at q=(pi,pi), whose spectral weight vanishes as a linear and quadratic function of the momentum respectively. The low-energy collective modes contain fluctuations of nematic-director, spin, and gauge degrees of freedom. Associated with the gapless q-linear modes, we evaluate the temperature dependence of the nuclear spin relaxation rate 1/T1 in the low-temperature regime as 1/T1 \propto T^{2d-1}, where d is the effective spatial dimension.

25 pages, 15 figures; a new section is included, where low-temperature dependence of the NMR relaxation rate is discussed

References in corpus (14)

• Vector chiral and multipolar orders in the spin-1/2 frustrated ferromagnetic chain in magnetic field
• Emergent multipolar spin correlations in a fluctuating spiral - The frustrated ferromagnetic S=1/2 Heisenberg chain in a magnetic field
• New high magnetic field phase of the frustrated $S=1/2$ chain compound LiCuVO${}_4$
• Correlation functions and excitation spectrum of the frustrated ferromagnetic spin-1/2 chain in an external magnetic field
• Evidence of a bond-nematic phase in LiCuVO4
• Spin-Nematic and Spin-Density-Wave Orders in Spatially Anisotropic Frustrated Magnets in a Magnetic Field
• NMR relaxation rate and dynamical structure factors in nematic and multipolar liquids of frustrated spin chains under magnetic fields
• The modulated spin liquid: a new paradigm for URu${}_2$Si${}_2$
• Field and temperature dependence of the NMR relaxation rate in the magnetic quadrupolar liquid phase of spin-1/2 frustrated ferromagnetic chains
• Angle-resolved NMR: quantitative theory of 75As T1 relaxation rate in BaFe2As2
• Spin nematic order in multiple-spin exchange models on the triangular lattice
• Projective studies of spin nematics in a quantum frustrated ferromagnet
• Spin nematic phase in (quasi-)one-dimensional frustrated magnet in strong magnetic field
• Nematic order in the multiple-spin exchange model on the triangular lattice

Cited by in corpus (18)

• Waves in the unseen : theory of spin excitations in a quantum spin nematic
• Dynamical structure factor of the triangular antiferromagnet: the Schwinger boson theory beyond the mean field approach
• Competing spin liquids and hidden nematic order in spin ice with frustrated transverse exchange
• Excitations and quasi-one-dimensionality in field-induced nematic and spin density wave states
• Ghost in the machine: Theory of inelastic neutron scattering in a field-induced spin-nematic state
• Spectral evidence of a ghostly transition: Theory of NMR 1/T_1 relaxation in a quantum spin nematic in applied magnetic field
• Putative spin-nematic phase in BaCdVO(PO${}_4$)${}_2$
• Electron spin resonance for the detection of long-range spin nematic order
• Magnetic structure and spin waves in the frustrated ferro-antiferromagnet Pb${}_2$VO(PO${}_4$)${}_2$
• Two-photon driven magnon-pair resonance as a signature of spin-nematic order
• Magnetically hidden state on the ground floor of the magnetic Devil's staircase
• The Quantum Cluster Variational Method and the Phase Diagram of the quantum ferromagnetic $J_1$-$J_2$ model
• Field-induced spin nematic Tomonaga-Luttinger liquid of the $S=1/2$ spin ladder system with the anisotropic ferromagnetic rung interaction
• Finite temperature thermodynamic properties of the spin-1 nematics in an applied magnetic field
• Possible Observation of Quadrupole Waves in Spin Nematics
• RVB signatures in the spin dynamics of the square-lattice Heisenberg antiferromagnet
• Dynamical structure factors in the nematic phase of frustrated ferromagnetic spin chains
• Dynamics of quantum spin-nematics: Comparisons with canted antiferromagnets