Comparison of GW band structure to semiempirical approach for an FeSe monolayer

Journal Article · Mon Jun 22 00:00:00 EDT 2020 · Physical Review B

DOI:https://doi.org/10.1103/physrevb.101.235154· OSTI ID:1695734

Qiu, Diana Y. ^[1]; Coh, Sinisa ^[2]; Cohen, Marvin L. ^[3]; Louie, Steven G. ^[3]

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1. Univ. of California, Berkeley, CA (United States); Yale Univ., New Haven, CT (United States)
2. Univ. of California, Riverside, CA (United States)
3. Univ. of California, Berkeley, CA (United States)

We present the $G_0{W}_0$ band structure, core levels, and deformation potential of monolayer FeSe in the paramagnetic phase based on a starting mean field of the Kohn-Sham density functional theory (DFT) with the Perdew, Burke, and Ernzerhof functional. We find the GW correction increases the bandwidth of the states forming the $M$ pocket near the Fermi energy, while leaving the $\mathrm{\Gamma }$ pocket roughly unchanged. We then compare the $G_0{W}_0$ quasiparticle band energies with the band structure from a simple empirical $+\mathrm{A}$ approach, which was recently proposed to capture the renormalization of the electron-phonon interaction going beyond DFT in FeSe, when used as a starting point in density functional perturbation theory. We show that this empirical correction succeeds in approximating the GW nonlocal and dynamical self-energy in monolayer FeSe and reproduces the GW band structure near the Fermi surface, the core energy levels, and the deformation potential (electron-phonon coupling).

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1695734
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 23 Vol. 101; ISSN 2469-9950
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
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