Povzetek
Quadratic Hamiltonians that exhibit single-particle quantum chaos are called quantum-chaotic quadratic Hamiltonians. One of their hallmarks is single-particle eigenstate thermalization introduced in Łydżba et al. [Phys. Rev. B 104, 214203 (2021)], which describes statistical properties of matrix elements of observables in single-particle eigenstates. However, the latter has been studied only in quantum-chaotic quadratic Hamiltonians that obey the U(1) symmetry. Here, we focus on quantum-chaotic quadratic Hamiltonians that break the U(1) symmetry and, hence, their “single-particle” eigenstates are actually single-quasiparticle excitations introduced on the top of a many-body state. We study their wave functions and matrix elements of one-body observables, for which we introduce the notion of single-quasiparticle eigenstate thermalization. Focusing on spinless fermion Hamiltonians in three dimensions with local hopping, pairing, and on-site disorder, we also study the properties of disorder-induced near zero modes, which give rise to a sharp peak in the density of states at zero energy. Finally, we numerically show equilibration of observables in many-body eigenstates after a quantum quench. We argue that the latter is a consequence of single-quasiparticle eigenstate thermalization, in analogy to the U(1) symmetric case from Łydżba et al. [Phys. Rev. Lett. 131, 060401 (2023)].
Ključne besede
statistična fizika;statistical physics;
Podatki
| Jezik: |
Angleški jezik |
| Leto izida: |
2024 |
| Tipologija: |
1.01 - Izvirni znanstveni članek |
| Organizacija: |
UL FMF - Fakulteta za matematiko in fiziko |
| UDK: |
536.9 |
| COBISS: |
193901571
|
| ISSN: |
2470-0045 |
| Št. ogledov: |
29 |
| Št. prenosov: |
3 |
| Ocena: |
0 (0 glasov) |
| Metapodatki: |
|
Ostali podatki
| Sekundarni jezik: |
Slovenski jezik |
| Sekundarne ključne besede: |
statistična fizika; |
| Vrsta dela (COBISS): |
Članek v reviji |
| Strani: |
str. 024102-1-024102-17 |
| Letnik: |
ǂVol. ǂ109 |
| Zvezek: |
ǂiss. ǂ2 |
| Čas izdaje: |
2024 |
| DOI: |
10.1103/PhysRevE.109.024102 |
| ID: |
23530191 |