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Dynamics of lattice pinned charge stripes

Y. A. Dimashko·C. Morais Smith·N. Hasselmann·A. O. Caldeira
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Abstract

We study the transversal dynamics of a charged stripe (quantum string) and show that zero temperature quantum fluctuations are able to depin it from the lattice. If the hopping amplitude t is much smaller than the string tension J, the string is pinned by the underlying lattice. At t>>J, the string is depinned and allowed to move freely, if we neglect the effect of impurities. By mapping the system onto a 1D array of Josephson junctions, we show that the quantum depinning occurs at t/J = 2 / pi^2. Besides, we exploit the relation of the stripe Hamiltonian to the sine-Gordon theory and calculate the infrared excitation spectrum of the quantum string for arbitrary t/J values.

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Y. A. Dimashko, C. Morais Smith, N. Hasselmann, A. O. Caldeira. 1999-12-06. Dynamics of lattice pinned charge stripes. https://doi.org/10.1103/physrevb.60.88

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