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Published on: March 30, 2017
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Finite temperature effects in quantum systems with competing scalar orders
Nei Lopes1, Daniel G Barci2, Mucio A Continentino1
1Centro Brasileiro de Pesquisas Físicas, Rua Dr Xavier Sigaud 150, Urca, 22290-180, Rio de Janeiro, Brazil.
Summary
Thermal fluctuations in many-body systems drive weak first-order phase transitions, destabilizing coexisting phases. Above the critical temperature (Tc), systems exhibit quantum critical scaling, with specific heat revealing a gap below Tc.
Area of Science:
- Condensed matter physics
- Quantum field theory
- Statistical mechanics
Background:
- Investigating competing ground states in many-body systems is crucial.
- Quantum fluctuations influence phase competition based on coupling, dynamics, and dimensionality.
Purpose of the Study:
- To incorporate thermal fluctuations into the effective potential of systems with competing order parameters.
- To study the impact of thermal fluctuations on phase transitions and critical behavior.
Main Methods:
- Application of the Matsubara summation technique from finite temperature quantum field theory.
- Analysis of two- and three-dimensional materials with Lorentz invariant quantum critical theory (z=1).
Main Results:
- Thermal fluctuations induce weak first-order temperature phase transitions.
- Coexisting phases arising from quantum corrections become unstable at these transitions.
- Above the critical temperature (Tc), systems show scaling behavior consistent with approaching a quantum critical point.
- Below Tc, specific heat exhibits a thermally activated contribution with a gap.
Conclusions:
- The critical temperature (Tc) decreases with distance from the zero temperature classical bicritical point (ZTCBP).
- The highest Tc is achieved above the fine-tuned ZTCBP value in this theoretical framework.
Keywords:
Lorentz invariant quantum critical theorycompeting scalar ordersquantum systemsscaling regimethermal and quantum fluctuationsweak first-order transitionMore Related Videos
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