Quantum localization measures in phase space
نویسندگان
چکیده
Measuring the degree of localization quantum states in phase space is essential for description dynamics and equilibration systems, but this topic far from being understood. There no unique way to measure localization, individual measures can reflect different aspects same state. Here we present a general scheme define spaces, which based on what call R\'enyi occupations, any be derived. We apply four-dimensional unbounded interacting spin-boson Dicke model. In particular, make detailed comparison two Husimi function regime where model chaotic, namely, one that projects over finite spin another uses defined classical energy shells. elucidate origin their differences, showing spaces definition maximal delocalization requires bounded reference subspace, with selections leading contextual answers.
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ژورنال
عنوان ژورنال: Physical Review E
سال: 2021
ISSN: ['1550-2376', '1539-3755']
DOI: https://doi.org/10.1103/physreve.103.052214