The Wiedemann-Franz law in doped Mott insulators without quasiparticles

• 成果类型: Article
• 署名作者: Wang, Wen O.; Ding, Jixun K.; Schattner, Yoni; Huang, Edwin W.; Moritz, Brian; Devereaux, Thomas P.
• 署名单位: Stanford University; Stanford University; United States Department of Energy (DOE); SLAC National Accelerator Laboratory; Stanford University; University of Illinois System; University of Illinois Urbana-Champaign; University of Illinois System; University of Illinois Urbana-Champaign; University of Notre Dame; University of Notre Dame; Stanford University; Stanford University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8582
• DOI: 10.1126/science.ade3232
• 发表日期: 2023-12-01
• 页码: 1070-1073
• 关键词: magnetoresistance; conductivity

摘要

Many metallic quantum materials display anomalous transport phenomena that defy a Fermi liquid description. Here, we use numerical methods to calculate thermal and charge transport in the doped Hubbard model and observe a crossover separating high- and low-temperature behaviors. Distinct from the behavior at high temperatures, the Lorenz number L becomes weakly doping dependent and less sensitive to parameters at low temperatures. At the lowest numerically accessible temperatures, L roughly approaches the Wiedemann-Franz constant L-0, even in a doped Mott insulator that lacks well-defined quasiparticles. Decomposing the energy current operator indicates a compensation between kinetic and potential contributions, which may help to clarify the interpretation of transport experiments beyond Boltzmann theory in strongly correlated metals.