Complexity of quantum states in the twodimensional pairing model
(2012) In Physical Review E (Statistical, Nonlinear, and Soft Matter Physics) 86(6). Abstract
 It is known that manyfermion systems, such as complex atoms and nuclei, reveal (at some level of excitation energy) local signatures of quantum chaos similar to the predictions of random matrix theory. Here, we study the gradual development of such signatures in a model system of up to 16 fermions interacting through shortrange pairingtype forces in a twodimensional harmonic trap. We proceed from the simplest characteristics of the level spacing distribution to the complexity of eigenstates, strength, and correlation functions. For increasing pairing strength, at first, chaotic signatures gradually appear. However, when the pairing force dominates the Hamiltonian, we see a regression towards regularity. We introduce a "phase... (More)
 It is known that manyfermion systems, such as complex atoms and nuclei, reveal (at some level of excitation energy) local signatures of quantum chaos similar to the predictions of random matrix theory. Here, we study the gradual development of such signatures in a model system of up to 16 fermions interacting through shortrange pairingtype forces in a twodimensional harmonic trap. We proceed from the simplest characteristics of the level spacing distribution to the complexity of eigenstates, strength, and correlation functions. For increasing pairing strength, at first, chaotic signatures gradually appear. However, when the pairing force dominates the Hamiltonian, we see a regression towards regularity. We introduce a "phase correlator" that allows us to distinguish the complexity of a quantum state that originates from its collective nature, from the complexity originating from quantum chaos. DOI: 10.1103/PhysRevE.86.066204 (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/record/3372368
 author
 Armstrong, J. R.; Åberg, Sven ^{LU} ; Reimann, Stephanie ^{LU} and Zelevinsky, V. G.
 organization
 publishing date
 2012
 type
 Contribution to journal
 publication status
 published
 subject
 in
 Physical Review E (Statistical, Nonlinear, and Soft Matter Physics)
 volume
 86
 issue
 6
 publisher
 American Physical Society
 external identifiers

 wos:000311929000004
 scopus:84871427763
 ISSN
 15393755
 DOI
 10.1103/PhysRevE.86.066204
 language
 English
 LU publication?
 yes
 id
 d145006cbb8b459ea5f30a46393ec2f3 (old id 3372368)
 date added to LUP
 20130201 12:34:24
 date last changed
 20190402 01:02:37
@article{d145006cbb8b459ea5f30a46393ec2f3, abstract = {It is known that manyfermion systems, such as complex atoms and nuclei, reveal (at some level of excitation energy) local signatures of quantum chaos similar to the predictions of random matrix theory. Here, we study the gradual development of such signatures in a model system of up to 16 fermions interacting through shortrange pairingtype forces in a twodimensional harmonic trap. We proceed from the simplest characteristics of the level spacing distribution to the complexity of eigenstates, strength, and correlation functions. For increasing pairing strength, at first, chaotic signatures gradually appear. However, when the pairing force dominates the Hamiltonian, we see a regression towards regularity. We introduce a "phase correlator" that allows us to distinguish the complexity of a quantum state that originates from its collective nature, from the complexity originating from quantum chaos. DOI: 10.1103/PhysRevE.86.066204}, articleno = {066204}, author = {Armstrong, J. R. and Åberg, Sven and Reimann, Stephanie and Zelevinsky, V. G.}, issn = {15393755}, language = {eng}, number = {6}, publisher = {American Physical Society}, series = {Physical Review E (Statistical, Nonlinear, and Soft Matter Physics)}, title = {Complexity of quantum states in the twodimensional pairing model}, url = {http://dx.doi.org/10.1103/PhysRevE.86.066204}, volume = {86}, year = {2012}, }