Density of Neutral Solitons in Weakly Disordered Peierls Chains

Abstract

We study the effects of weak off-diagonal disorder on Peierls systems with a doubly degenerate ground state. We show that for these systems disorder in the electron hopping amplitudes induces a finite density of solitons in the minimal-energy lattice configuration of a single chain. These disorder-induced dimerization kinks are neutral and have spin 1/2. Using a continuum model for the Peierls chain and treating the lattice classically, we analytically calculate the average free energy and density of kinks. We compare these results to numerical calculations for a discrete model and discuss the implications of the kinks for the optical and magnetic properties of the conjugated polymer trans-polyacetylene.

28 pages, revtex, 5 Postscript figures, to appear in Phys. Rev. B

References in corpus (2)

• Disorder-induced solitons in conjugated polymers
• Instanton in Disordered Peierls Systems

Cited by in corpus (4)

• Magnetic light scattering in low-dimensional quantum spin systems
• Critical temperature and density of spin-flips in the anisotropic random field Ising model
• Coherently delocalized states in dipole interacting Rydberg ensembles: the role of internal degeneracies
• Magnetic Susceptibility Due to Disorder-Induced Neutral Solitons in Interacting Polymer Chains