Antiferromagnetism and Superconductivity in UPt_3

Anupam Garg

doi:10.1088/0953-8984/10/19/020

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arXiv · cond-mat/9803311

Antiferromagnetism and Superconductivity in UPt_3

Anupam Garg

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Abstract

The short ranged antiferromagnetism recently seen in UPt_3 is proved incompatible with two dimensional (2D) order parameter models that take the antiferromagnetism as a symmetry breaking field. To adjust to the local moment direction, the order parameter twists over very long length scales as per the Imry-Ma argument. A variational solution to the Ginzburg-Landau equations is used to study the nature of the short ranged order. Although there are still two transitions, the lower one is of first order -- in contradiction to experiments. It is shown that the latent heat predicted by the 2D models at the lower transition is too large not to have been seen. A simple periodic model is numerically studied to show that the lower transition can not be a crossover either.

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BibTeX RIS

Anupam Garg. 1998-03-25. Antiferromagnetism and Superconductivity in UPt_3. https://doi.org/10.1088/0953-8984%2F10%2F19%2F020

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