A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Interacting Electrons in a Flat‐Band System within the Generalized Kadanoff–Baym Ansatz (2024)
Cosco, F., Tuovinen, R., & Lo Gullo, N. (2024). Interacting Electrons in a Flat‐Band System within the Generalized Kadanoff–Baym Ansatz. Physica Status Solidi B : Basic Research, Early View. https://doi.org/10.1002/pssb.202300561
JYU-tekijät tai -toimittajat
Julkaisun tiedot
Julkaisun kaikki tekijät tai toimittajat: Cosco, Francesco; Tuovinen, Riku; Lo Gullo, Nicolino
Lehti tai sarja: Physica Status Solidi B : Basic Research
ISSN: 0370-1972
eISSN: 1521-3951
Julkaisuvuosi: 2024
Ilmestymispäivä: 19.03.2024
Volyymi: Early View
Kustantaja: Wiley-VCH Verlag
Julkaisumaa: Saksa
Julkaisun kieli: englanti
DOI: https://doi.org/10.1002/pssb.202300561
Julkaisun avoin saatavuus: Ei avoin
Julkaisukanavan avoin saatavuus:
Julkaisu on rinnakkaistallennettu (JYX): https://jyx.jyu.fi/handle/123456789/94513
Rinnakkaistallenteen verkko-osoite (pre-print): https://arxiv.org/abs/2402.15378
Tiivistelmä
In this work, the study of the spectral properties of an open interacting system by solving the generalized Kadanoff-Baym ansatz (GKBA) master equation for the single-particle density matrix, namely the time-diagonal lesser Green's function, is reported. To benchmark its validity, the solution obtained within the GKBA is compared with the solution of the Dyson equation at stationarity. In both approaches, the interaction is treated within the self-consistent second-order Born approximation, whereas the GKBA still retains the retarded propagator calculated at the Hartree–Fock (HF) and wideband limit approximation level. The model chosen is that of two leads connected through a central correlated region where particles can interact and utilize the stationary particle current at the boundary of the junction as a probe of the spectral features of the system. The central region is chosen as the simplest model featuring a degenerate ground state with a flat band. The main result is that the solution of the GKBA master equation captures well the spectral feature of such system and specifically the transition from dispersionless to dispersive behavior of the flat band as the interaction is increased. Therefore, the GBKA solution retains the main spectral features of the self-energy used even when the propagator is at the HF level.
YSO-asiasanat: kvanttifysiikka; kiinteän olomuodon fysiikka; elektronit; matemaattiset mallit; osittaisdifferentiaaliyhtälöt; numeerinen analyysi
Vapaat asiasanat: flat bands; generalized Kadanoff–Baym ansatz; quantum transports
Liittyvät organisaatiot
OKM-raportointi: Kyllä
Raportointivuosi: 2024
Alustava JUFO-taso: 1
