dorsal/arxiv
View SchemaGround state fidelity and quantum phase transitions in free Fermi systems
| Authors | P. Zanardi, M. Cozzini, P. Giorda |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0606130 |
| URL | https://arxiv.org/abs/quant-ph/0606130 |
| DOI | 10.1088/1742-5468/2007/02/L02002 |
Abstract
We compute the fidelity between the ground states of general quadratic fermionic hamiltonians and analyze its connections with quantum phase transitions. Each of these systems is characterized by a $L\times L$ real matrix whose polar decomposition, into a non-negative $\Lambda$ and a unitary $T$, contains all the relevant ground state (GS) information. The boundaries between different regions in the GS phase diagram are given by the points of, possibly asymptotic, singularity of $\Lambda$. This latter in turn implies a critical drop of the fidelity function. We present general results as well as their exemplification by a model of fermions on a totally connected graph.
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"abstract": "We compute the fidelity between the ground states of general quadratic\nfermionic hamiltonians and analyze its connections with quantum phase\ntransitions. Each of these systems is characterized by a $L\\times L$ real\nmatrix whose polar decomposition, into a non-negative $\\Lambda$ and a unitary\n$T$, contains all the relevant ground state (GS) information. The boundaries\nbetween different regions in the GS phase diagram are given by the points of,\npossibly asymptotic, singularity of $\\Lambda$. This latter in turn implies a\ncritical drop of the fidelity function. We present general results as well as\ntheir exemplification by a model of fermions on a totally connected graph.",
"arxiv_id": "quant-ph/0606130",
"authors": [
"P. Zanardi",
"M. Cozzini",
"P. Giorda"
],
"categories": [
"quant-ph",
"cond-mat.str-el"
],
"doi": "10.1088/1742-5468/2007/02/L02002",
"title": "Ground state fidelity and quantum phase transitions in free Fermi systems",
"url": "https://arxiv.org/abs/quant-ph/0606130"
},
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