Lattice Dimerization in the Spin-Peierls Compound CuGeO${}_3$

Abstract

The uniaxial pressure dependences of the exchange coupling and the structural distortion in the dimerized phase of CuGeO${}_3$ are analyzed. A minimum magnetic dimerization of 3 % is obtained, incompatible with an adiabatic approach to the spin-Peierls transition. Exploring the properties of an Heisenberg spin chain with dynamical spin-phonon coupling, the dimerization dependence of the spin excitation gap is found to be in qualitative agreement with experiment.

2 pages, 1 figure included

References in corpus (2)

• Reexamination of the microscopic couplings of the quasi one-dimensional antiferromagnet CuGeO_3
• Peierls Dimerization with Non-Adiabatic Spin-Phonon Coupling

Cited by in corpus (11)

• The microscopic spin-phonon coupling constants in CuGeO_3
• Quantum lattice fluctuations in a frustrated Heisenberg spin-Peierls chain
• Adiabatic-antiadiabatic crossover in a spin-Peierls chain
• Density waves in strongly correlated quantum chains
• Lattice dynamical effects on the Peierls transition in one-dimensional metals and spin chains
• Soliton Lattices in the Incommensurate Spin-Peierls Phase: Local Distortions and Magnetizations
• Excitation Spectra of Structurally Dimerized and Spin-Peierls Chains in a Magnetic Field
• Magneto-elastic excitations in spin-Peierls systems
• Triplet Dispersion in CuGeO_3: Perturbative Analysis
• Optical spectroscopy of pure and doped CuGeO3
• Dynamical phase transition in a strongly hybridized phonon-triplon chain