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arXiv · 0809.3856

Density-functional fidelity approach to quantum phase transitions

Shi-Jian Gu
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Abstract

We propose a new approach to quantum phase transitions in terms of the density-functional fidelity, which measures the similarity between density distributions of two ground states in parameter space. The key feature of the approach, as we will show, is that the density-functional fidelity can be measured easily in experiments. Both the validity and versatility of the approach are checked by the Lipkin-Meshkov-Glick model and the one-dimensional Hubbard model.

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Shi-Jian Gu. 2008-09-23. Density-functional fidelity approach to quantum phase transitions. https://doi.org/10.1088/0256-307x%2F26%2F2%2F026401

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