Giant phonon anomalies in the pseudo-gap phase of TiOCl

Abstract

We report infrared and Raman spectroscopy results of the spin-1/2 quantum magnet TiOCl. Giant anomalies are found in the temperature dependence of the phonon spectrum, which hint to unusual coupling of the electronic degrees of freedom to the lattice. These anomalies develop over a broad temperature interval, suggesting the presence of an extended fluctuation regime. This defines a pseudo-gap phase, characterized by a local spin-gap. Below 100 K a dimensionality cross-over leads to a dimerized ground state with a global spin-gap of about 2${\Delta }_{spin}\approx$~430 K.

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References in corpus (15)

• Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors
• Orbital liquid in three dimensional Mott insulator: $LaTi{O}_3$
• Magnetic light scattering in low-dimensional quantum spin systems
• S=1/2 chains and spin-Peierls transition in TiOCl
• Alternating Spin and Orbital Dimerization in Strong-coupling Two-band Models
• Charged Magnons in NaV2O5
• Evidence for an unconventional magnetic instability in the spin-tetrahedra system Cu_2Te_2O_5Br_2
• Charge and Spin Dynamics of an Ordered Stripe Phase in La_(1 2/3)Sr_(1/3)NiO_4 by Raman Spectroscopy
• Orbital order in the low-dimensional quantum spin system TiOCl probed by ESR
• Magnetism of a tetrahedral cluster spin-chain
• Numerical Study of the One-Dimensional Spin-Orbit Coupled System with SU(2)$\otimes$SU(2) Symmetry
• TiOCl, an orbital-ordered system?
• Infrared optical properties of the spin-1/2 quantum magnet $TiOCl$
• Elementary excitations in one-dimensional spin-orbital models: neutral and charged solitons and their bound states
• Charge order induced sharp Raman peak in Sr_14Cu_24O_41

Cited by in corpus (25)

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• Optical study of orbital excitations in transition-metal oxides
• Crossover from coherent to incoherent scattering in spin-orbit dominated Sr2IrO4
• Incommensurate interactions and non-conventional spin-Peierls transition in TiOBr
• Pressure-induced insulator-to-metal transition in low-dimensional TiOCl
• Heat capacity of the quantum magnet TiOCl
• Spin dynamics in the low-dimensional magnet TiOCl
• Unusual quasi-one-dimensional electron dispersions in the spin-1/2 quantum magnet TiOCl
• X-ray Scattering Study of the spin-Peierls transition and soft phonon behavior in TiOCl
• Correlation effects on the electronic structure of TiOCl: a NMTO+DMFT study
• Symmetry disquisition on the TiOX phase diagram
• Muon-spin relaxation measurements on the dimerized spin-1/2 chains NaTiSi2O6 and TiOCl
• Spin gap formation in the quantum spin systems TiOX, X=Cl and Br
• Ab-initio Phonon Calculations for the layered compound TiOCl
• One-dimensional versus two-dimensional correlation effects in the oxyhalides TiOCl and TiOBr
• Magnetization and specific heat of the dimer system CuTe2O5
• Ab initio computation of d-d excitation energies in low-dimensional Ti and V oxychlorides
• Density functional study of the electronic and vibrational properties of TiOCl
• Cluster Dynamical Mean-field calculations for TiOCl
• Singlet-Triplet Excitations in the Unconventional Spin-Peierls System TiOBr
• Lattice and orbital fluctuations in TiPO4
• Unoccupied electronic structure of TiOCl studied by x-ray absorption near-edge spectroscopy
• High pressure x-ray study of spin-Peierls physics in the quantum spin chain material TiOCl
• Incommensurate spin Luttinger liquid phase in a model for the spin-Peierls materials TiOBr and TiOCl
• Analysis of the behavior of singlet pairs in inorganic crystal XOCl(X=Ti,Bi)