Hydrogen-Like Absorption Spectrum of Cuprous Oxide

Excitonic giant-dipole potentials in cuprous oxide

“…Excitons consist of a negatively charged electron in the conduction band and a positively charged hole in the valence band. As the interaction between the two species can be modeled as a screened Coulomb interaction, excitons are often considered to be a solid-state quasi-particle analogue to the hydrogen atom [3][4][5]. In particular, excitons in cuprous oxide (Cu 2 O) have attracted quite some attention in recent years due to an outstanding experiment, in which the hydrogen-like absorption spectrum of these quasiparticles could be observed up to principal quantum numbers n = 25 [6].…”

Cuprous Oxide (Cu2O): A Unique System Hosting Various Excitonic Matter and Exhibiting Large Third-Order Nonlinear Optical Responses

“…The measured lifetime of quadrupole polaritons is about 2 ns and this much longer lifetime arises from the above noted dipole-forbidden nature of Cu 2 O. Being a coherent quantum superposition of a quadrupole exciton and a photon, this electron in the lowest conduction band ( 2 Γ + 6 ) and a hole in the highest valence band ( 2 Γ + 7 ), and shows a hydrogenic Rydberg series in the optical absorption spectrum [Hayashi & Katsuki (1952)]. Including so-called central cell corrections [Kavoulakis et al (1997)], a spectroscopic fit to the observed Rydberg series reveals a tightly bound 1s excitonic state with a binding energy of 153 meV, corresponding to Bohr radius of 0.7 nm.…”

Anisotropic effective mass of orthoexcitons in Cu2O

“…1 In the beginning, there were mainly the Leningrad 2 and the Strasbourg group 3 who studied many details in the rich spectra of the lowest exciton series. It is termed the yellow series though it starts in the red (about 610 nm) but reaches out into the yellow (570 nm) with a perfect hydrogenlike P series from n = 2 to n = 12.…”