Vortex lines in the three-dimensional XY model with random phase shifts.
نویسندگان
چکیده
The stability of the ordered phase of the three-dimensional XY model with random phase shifts is studied by considering the roughening of a single stretched vortex line due to disorder. It is shown that the vortex line may be described by a directed polymer Hamiltonian with an effective random potential that is long-range correlated. A Flory argument estimates the roughness exponent to z53/4 and the energy fluctuation exponent to v51/2, thus fulfilling the scaling relation v52z21. The Schwartz-Edwards method as well as a numerical integration of the corresponding Burger’s equation confirms this result. Since z,1, the ordered phase of the original XY model is stable. @S0163-1829~96!00945-9#
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 54 22 شماره
صفحات -
تاریخ انتشار 1996