Ground states versus low-temperature equilibria in random field Ising chains

G. Schröder; T. Knetter; M. J. Alava; H. Rieger

doi:10.1007/s100510170027

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Ground states versus low-temperature equilibria in random field Ising chains

G. Schröder·T. Knetter·M. J. Alava·H. Rieger

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Abstract

We discuss with the aid of random walk arguments and exact numerical computations the magnetization properties of one-dimensional random field chains. The ground state structure is explained in terms of absorbing and non-absorbing random walk excursions. At low temperatures, the magnetization profiles follow those of the ground states except at regions where a local random field fluctuation makes thermal excitations feasible. This follows also from the non-absorbing random walks, and implies that the magnetization length scale is a product of these two scales. It is not simply given by the Imry-Ma-like ground state domain size nor by the scale of the thermal excitations.

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BibTeX RIS

G. Schröder, T. Knetter, M. J. Alava, H. Rieger. 2000-10-13. Ground states versus low-temperature equilibria in random field Ising chains. https://doi.org/10.1007/s100510170027

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