Mechanisms for Sub-Gap Optical Conductivity in Herbertsmithite

Abstract

Recent terahertz conductivity measurements observed low-power-law frequency dependence of optical conduction within the Mott gap of the Kagome lattice spin-liquid candidate Herbertsmithite. We investigate mechanisms for this observed sub-gap conductivity for two possible scenarios in which the ground-state is described by: 1) a U(1) Dirac spin-liquid with emergent fermionic spinons or 2) a nearly critical Z2 spin-liquid in the vicinity of a continuous quantum phase transition to magnetic order. We identify new mechanisms for optical-absorption via magneto-elastic effects and spin- orbit coupling. In addition, for the Dirac spin-liquid scenario, we establish an explicit microscopic origin for previously proposed absorption mechanisms based on slave-particle effective field theory descriptions.

15 pages, 4 figures; v2 - references updated

References in corpus (17)

• Fractionalized excitations in the spin liquid state of a kagomé lattice antiferromagnet
• Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
• Quantum Hall Ferromagnetism in Graphene
• Projected wavefunction study of Spin-1/2 Heisenberg model on the Kagome lattice
• Spin Filtered Edge States and Quantum Hall Effect in Graphene
• Gapless spin-liquid phase in the kagome spin-1/2 Heisenberg antiferromagnet
• Properties of an algebraic spin liquid on the kagome lattice
• 17O NMR study of the intrinsic magnetic susceptibility and spin dynamics of the quantum kagome antiferromagnet ZnCu3(OH)6Cl2
• Graphene integer quantum Hall effect in the ferromagnetic and paramagnetic regimes
• Electronic Orbital Currents and Polarization in Mott Insulators
• ^{63}Cu, ^{35}Cl, and ^{1}H NMR in the S=1/2 Kagomé Lattice ZnCu_{3}(OH)_{6}Cl_{2}
• Spin liquids on a honeycomb lattice: Projective Symmetry Group study of Schwinger fermion mean-field theory
• $Z_2$ spin liquid and chiral antiferromagnetic phase in Hubbard model on the honeycomb lattice: duality between Schwinger-fermion and Schwinger-boson representations
• Quantum criticality of the kagome antiferromagnet with Dzyaloshinskii-Moriya interactions
• Power-law Conductivity inside the Mott gap: application to $\kappa -(BEDT-TTF{)}_{2}C{u}_2(CN{)}_3$
• Power-law dependence of the optical conductivity observed in the quantum spin-liquid compound κ-(BEDT-TTF)2Cu2(CN)3
• A Proposal to Use Neutron Scattering to Measure Scalar Spin Chirality Fluctuations in Kagome Lattices

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