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Statistics of lowest excitations in two dimensional Gaussian spin glasses

M. Picco·F. Ritort·M. Sales
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Abstract

A detailed investigation of lowest excitations in two-dimensional Gaussian spin glasses is presented. We show the existence of a new zero-temperature exponent lambda describing the relative number of finite-volume excitations with respect to large-scale ones. This exponent yields the standard thermal exponent of droplet theory theta through the relation, theta=d(lambda-1). Our work provides a new way to measure the thermal exponent theta without any assumption about the procedure to generate typical low-lying excitations. We find clear evidence that theta < theta_{DW} where theta_{DW} is the thermal exponent obtained in domain-wall theory showing that MacMillan excitations are not typical.

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M. Picco, F. Ritort, M. Sales. 2001-09-10. Statistics of lowest excitations in two dimensional Gaussian spin glasses. https://doi.org/10.1103/physrevb.67.184421

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