Quantum stabilization and decay of correlations in anharmonic crystals (Q1417854)

For quantum crystals with harmonic interactions and with one-site double-well anharmonic potentials growing at infinity faster than quadratic, there exists a light-mass domain, where decay of correlation functions is the same as for harmonic quantum crystals. This (quantum stabilization) phenomenon is known since \textit{A. Verbeure} and \textit{V. A. Zagrebnov} [J. Phys. A, Math. Gen. 28, No. 18, 5415--5421 (1995; Zbl 0871.46043)] as no-go theorem for quantum structural phase transitions.