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arXiv · 2004.00029

Paradigm shift for quantum paraelectric: softening of longitudinal modes

Yaron Kedem
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Abstract

We revisit the quantum phase transition from a paraelectric state to a ferroelectric one and in particular the widespread distinction between a longitudinal modes to transverse one. In contrast to transitions at finite temperature, for a quantum phase transition breaking a discrete symmetry the splitting between the modes is irrelevant. We show that an anisotropy in the context of a quantum phase transition leads to a different behavior, compared to a classical transition, and suggest an experiment to observe it. The result is essential for explaining the pairing mechanism in strontium titanate.

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Yaron Kedem. 2020-03-31. Paradigm shift for quantum paraelectric: softening of longitudinal modes. https://arxiv.org/abs/2004.00029

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