Universal Thermal Corrections to Symmetry-Resolved Entanglement Entropy and Full Counting Statistics

Understand

We consider the symmetry-resolved R\'{e}nyi and entanglement entropies for two-dimensional conformal field theories on a circle at nonzero temperature.

• We assume a unique ground state with a nonzero mass gap induced by the system's finite size and then calculate the leading corrections to the contributions of individual charge sectors in a low-temperature expansion.
• Besides the size of the mass gap and the degeneracy of the first excited state, these universal corrections depend only on the four-point correlation function of the primary fields.
• We also obtain thermal corrections to the full counting statistics of the ground state and define the \textit{probability fluctuations} function.