2024/01/24 by Yugo Onishi, Onishi, Yugo, Liang Fu +1 · 1 citation
Materials Science · Physics and Astronomy · #Electron and X-Ray Spectroscopy Techniques #Electronic and Structural Properties of Oxides #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Strongly Correlated Electrons (cond-mat.str-el) #Surface and Thin Film Phenomena
paper · pdf · doi:10.48550/arxiv.2401.13847
openalex publication_date 2024/01/24 · openalex created_date 2024/01/27 · openalex updated_date 2026/07/28
We introduce the concept of quantum weight as a fundamental property of insulating states of matter that is encoded in the ground-state static structure and measures quantum fluctuation in electrons' center of mass. We find a sum rule that directly relates quantum weight -- a ground state property -- with the negative-first moment of the optical conductivity above the gap frequency. Building on this connection to optical absorption, we derive both an upper bound and a lower bound on quantum weight in terms of electron density, dielectric constant, and energy gap. Therefore, quantum weight constitutes a key material parameter that can be experimentally determined from X-ray scattering.