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Quantum adiabatic cycles and their breakdown

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 نشر من قبل Nicolo Defenu Dr.
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Nicol`o Defenu




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An analytically solvable model for quasi-static transformations across quantum critical points featuring Bosonic quasi-particle excitations is presented. The model proves that adiabaticity breakdown is a general feature of universal slow dynamics in these systems. The existence of an anti-adiabatic dynamical phase with vanishing ground state fidelity in the slow drive limit is also proven. The relation of these findings with the Kibble-Zurek mechanism and their consequences on defect formation in many body systems ramped across a quantum phase transition are discussed.

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