Normal weak eigenstate thermalization

Łydżba, Patrycja (avtor), Świętek, Rafał (avtor), Mierzejewski, Marcin (avtor), Rigol, Marcos (avtor), Vidmar, Lev (avtor)

Eigenstate thermalization has been numerically shown to occur for few-body observables in a wide range of nonintegrable models. For intensive sums of few-body observables, a weaker version of eigenstate thermalization known as weak eigenstate thermalization has been proved to occur in general. Here, we unveil a stricter weak eigenstate thermalization phenomenon that occurs in quadratic models exhibiting quantum chaos in the single-particle sector (quantum-chaotic quadratic models) and in integrable interacting models. In such models, we argue that few-body observables that have a properly defined system-size independent norm are guaranteed to exhibit at least a polynomially vanishing variance (over the entire many-body energy spectrum) of the diagonal matrix elements, a phenomenon we dub normal weak eigenstate thermalization. We prove that normal weak eigenstate thermalization is a consequence of single-particle eigenstate thermalization, i.e., it can be viewed as a manifestation of quantum chaos at the single-particle level. We report numerical evidence of normal weak eigenstate thermalization for quantum-chaotic quadratic models such as the three-dimensional Anderson model in the delocalized regime and the power-law random banded matrix model, as well as for the integrable interacting spin-1/2 XYZ and XXZ models.

• Jezik: Angleški jezik
• Ključne besede: quantum chaos, thermalization, localization
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FMF - Fakulteta za matematiko in fiziko
• Status publikacije: Objavljeno
• Različica publikacije: Recenzirani rokopis
• Leto izida: 2024
• Št. strani: Str. 104202-1-104202-19
• Številčenje: Vol. 110, iss. 10
• PID: 20.500.12556/RUL-165854
• UDK: 538.9
• ISSN pri članku: 2469-9950
• DOI: 10.1103/PhysRevB.110.104202
• COBISS.SI-ID: 217686275
• Datum objave v RUL: 12.12.2024

Gradivo je del revije

• Naslov: Physical review
• Založnik: American Physical Society
• ISSN: 2469-9950
• COBISS.SI-ID: 2997348

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: kvantni kaos, termalizacija, lokalizacija