Identifying quantum phase transitions via geometric measures of nonclassicality

Abstract

It is shown that divergences in the susceptibility of any geometric measure of nonclassicality are sufficient conditions to identify phase transitions at arbitrary temperature. This establishes that geometric measures of nonclassicality, in any quantum resource theory, are generic tools to investigate phase transitions in quantum systems. For the zero-temperature case, we show that geometric measures of quantum coherence are especially useful for identifying first-order quantum phase transitions and can be a particularly robust alternative to other approaches employing measures of quantum correlations.