Band-Edge Quasiparticles from Electron-Phonon Coupling and Resistivity Saturation

Journal Article · 15 January 2019 · Physical Review Letters

DOI: https://doi.org/10.1103/physrevlett.122.026602 · OSTI ID:1609759

Perepelitsky, Edward ^[1]; Shastry, B. Sriram ^[2]

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1. Univ. of California, Santa Cruz, CA (United States); DOE/OSTI
2. Univ. of California, Santa Cruz, CA (United States)

We address the problem of resistivity saturation observed in materials such as the A-15 compounds. To do so, we calculate the resistivity for the Hubbard-Holstein model in infinite spatial dimensions to second order in on-site repulsion U ≤ D and to first order in (dimensionless) electron-phonon coupling strength λ ≤ 0.5, where D is the half bandwidth. We identify a unique mechanism to obtain two parallel quantum conducting channels: low-energy and band-edge high-energy quasi-particles. Here, we identify the source of the hitherto unremarked high-energy quasiparticles as a positive slope in the frequency dependence of the real part of the electron self-energy. In the presence of phonons, the self-energy grows linearly with the temperature at high T, causing the resistivity to saturate. As U is increased, the saturation temperature is pushed to higher values, offering a mechanism by which electron correlations destroy saturation.

• Research Organization: Univ. of California, Santa Cruz, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: FG02-06ER46319
• OSTI ID: 1609759
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 2 Vol. 122; ISSN 0031-9007; ISSN PRLTAO
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English