Uhlmann phase as a topological measure for one-dimensional fermion systems

O Viyuela1, A Rivas1, M A Martin-Delgado1

  • 1Departamento de Física Teórica I, Universidad Complutense, 28040 Madrid, Spain.

Summary

We introduce the Uhlmann geometric phase to characterize topological phases in 1D fermion systems, extending properties to finite temperatures. A critical temperature marks a sharp transition between distinct topological phases.

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