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Ground state structure of diluted antiferromagnets and random field systems

Alexander K. Hartmann
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Abstract

A method is presented for the calculation of all exact ground states of diluted antiferromagnets and random field systems in an arbitrary range of fields. It works by calculating all jump-fields B,Δwhere the system changes it's ground state. For each field value all degenerated ground states are represented by a set of (anti-) ferromagnetic clusters and a relation between the clusters. So a complete description of the ground state structure of these systems is possible. Systems are investigated up to size 48^3 on the whole field-range and up to 160^3 for some particular fields. The behavior of order parameters is investigated, the number of jumps is analyzed and the degree of degeneracy as functions of size and fields is calculated.

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Alexander K. Hartmann. 1997-04-04. Ground state structure of diluted antiferromagnets and random field systems. https://doi.org/10.1016/s0378-4371(97)00443-3

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