Pairing correlations and eigenvalues of two-body density matrix in atomic nuclei
arXiv:1911.04408 · doi:10.1016/j.aop.2019.168061
Abstract
The quantum phases of superconductivity and superfluidity are characterised mathematically by the Yang concept of Off-Diagonal Long Range Order (ODLRO), related to the existence of a large eigenvalue of the density matrix. We analyse how the Yang criterion applies for various Hamiltonians commonly employed to describe superfluid-type correlations in atomic nuclei. For like-particle pairing Hamiltonians the behaviour of the largest eigenvalue of two-body density matrix shows a clear evidence for a transition between a normal to a paired phase. However, this is not the case for the isoscalar proton-neutron pairing interactions acting in self-conjugate nuclei.
22 pages, 7 figures
References in corpus (6)
- Overview of Neutron-Proton Pairing
- Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei
- Mixed-Spin Pairing Condensates in Heavy Nuclei
- Accuracy of BCS-based approximations for pairing in small Fermi systems
- Isovector neutron-proton pairing with particle number projected BCS
- Isoscalar and isovector pairing in a formalism of quartets