Abstract
This article extends our previous analysis Stránský etal. (2014) of Excited-State Quantum Phase Transitions (ESQPTs) in systems of dimension two. We focus on the oscillatory component of the quantum state density in connection with ESQPT structures accompanying a first-order ground-state transition. It is shown that a separable (integrable) system can develop rather strong finite-size precursors of ESQPT expressed as singularities in the oscillatory component of the state density. The singularities originate in effectively 1-dimensional dynamics and in some cases appear in multiple replicas with increasing excitation energy. Using a specific model example, we demonstrate that these precursors are rather resistant to proliferation of chaotic dynamics.
Original language | English |
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Pages (from-to) | 57-82 |
Number of pages | 26 |
Journal | Annals of Physics |
Volume | 356 |
DOIs | |
State | Published - 1 May 2015 |
Bibliographical note
Publisher Copyright:© 2015.
Keywords
- Finite-size effects
- Oscillatory component of level density
- Quantum phase transitions
- Regular/chaotic dynamics