Quantum annealed criticality: A scaling description

Experimentally there exist many materials with first-order phase transitions at finite temperature that display quantum criticality. Classically, a strain-energy density coupling is known to drive first-order transitions in compressible systems, and here we generalize this Larkin et al. [Zh. Eksp. Teor. Fiz. 56, 1664 (1969) [Sov. Phys. JETP 29, 891 (1969)]] mechanism to the quantum case. We show that if the T = 0 system lies above its upper critical dimension, the line of first-order transitions ends in a “quantum annealed critical point” where zero-point fluctuations restore the underlying criticality of the order parameter. The generalized Larkin-Pikin phase diagram is presented and experimental consequences are discussed.