Year: 2026
Type: preprint
Abstract: We examined the energy-momentum relationship of the valence band of Cu$_2$O, which has gained interest as an emerging solid host for giant Rydberg states. Our findings reveal a nonparabolic dispersion, described using the rest mass (0.570 times the free electron mass) and rescaled light speed ($1.6\times 10^5$ m/s), which draws parallels with relativistic theory for high-energy particles. We propose a straightforward expression for the bound-state energies of Rydberg excitons with finite quantum defects, whose energy scheme deviates from the hydrogenic series. This formulation identifies relativistic kinematics as the physical origin of quantum defects, offering a streamlined basis for future studies on complex many-body correlations.
Source: arXiv (Cornell University)
Institutions: Kyoto University, Wakayama University
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Award: G1636631173
OpenAlex ID: W7223027874