Abstract
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-Pikin 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.
Highlights
The interplay of first-order phase transitions with quantum fluctuations is an active area [1,2,3,4,5,6,7,8] in the study of exotic quantum states near zero-temperature phase transitions [9,10,11,12,13,14,15]
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
We study a system with strainenergy density coupling [21] that has a line of first-order transitions at finite temperatures
Summary
The interplay of first-order phase transitions with quantum fluctuations is an active area [1,2,3,4,5,6,7,8] in the study of exotic quantum states near zero-temperature phase transitions [9,10,11,12,13,14,15]. At a first-order transition the quartic mode-mode coupling of the effective action becomes negative One mechanism for this phenomenon, studied by Larkin and Pikin [21] (LP), involves the interaction of strain with the fluctuating energy density of a critical order parameter. We derive the classical Larkin-Pikin criterion (1) as a macroscopic instability of the original (uncoupled) critical point with respect to the strainenergy density coupling [32] This approach can be rewritten in terms of correlation functions, giving insight into the Tc → 0 result. Derivations of the classical and quantum Larkin-Pikin actions and of various crossover scaling expressions are presented in five Appendices for interested readers
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
