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Paradigm shift for quantum paraelectric: softening of longitudinal modes

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 نشر من قبل Yaron Kedem
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Yaron Kedem




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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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