Cu${}_2$O Microcrystals Grown on Silicon as Platform for Quantum-Degenerate Excitons and Rydberg States

Abstract

Cuprous oxide (Cu${}_2$O) is a semiconductor with large exciton binding energy and significant technological importance in applications such as photovoltaics and solar water splitting. It is also a superior material system for quantum optics that enabled the observation of two intriguing phenomena, i.e. Rydberg excitons as solid-state analogue to highly-excited atomic states and dense exciton gases showing quantum degeneracy when approaching the phase transition to Bose-Einstein condensation. Previous experiments focused on natural bulk crystals due to major difficulties in growing high-quality synthetic samples. Here, we present Cu${}_2$O microcrystals with excellent optical material quality capable of hosting both quantum-degenerate excitons and excited Rydberg states. Growth of Cu${}_2$O with exceedingly low point defect levels was achieved on silicon by a scalable thermal oxidation process compatible with lithographic patterning. Using the latter, we demonstrate Rydberg excitons in site-controlled Cu${}_2$O microstructures, paving the way for a plethora of applications in integrated quantum photonics.

References in corpus (14)

• Giant Rydberg Excitons in Cuprous Oxide
• Atomistic details of oxide surfaces and surface oxidation: the example of copper and its oxides
• Nonlinear quantum optics mediated by Rydberg interactions
• Bose-Einstein Condensation of Excitons in Cu${}_2$O: Progress Over Thirty Years
• Transition to a Bose-Einstein condensate of excitons at sub-Kelvin temperatures
• Giant optical nonlinearities from Rydberg-excitons in semiconductor microcavities
• Rydberg excitons in the presence of an ultralow-density electron-hole plasma
• Condensation of Excitons in Cu2O at Ultracold Temperatures: Experiment and Theory
• Signatures of Quantum Coherence in Rydberg Excitons
• Single-photon source based on Rydberg exciton blockade
• Auger decay, Spin-exchange, and their connection to Bose-Einstein condensation of excitons in Cu_2O
• Vacancy Relaxation in Cuprous Oxide (Cu${}_{2-x}$O${}_{1-y}$)
• Decay and coherence of two-photon excited yellow ortho-excitons in Cu2O
• Evaluation of defects in cuprous oxide through exciton luminescence imaging

Cited by in corpus (17)

• Giant Rydberg excitons in Cu${}_2$O probed by photoluminescence excitation spectroscopy
• Electromagnetically induced transparency with Cu${}_2$O excitons in the presence of phonon coupling
• Quantum confined Rydberg excitons in Cu${}_2$O nanoparticles
• Plasma-enhanced interaction and optical nonlinearities of Cu${}_2$O Rydberg excitons
• Nonlinear Rydberg exciton-polaritons in Cu${}_2$O microcavities
• High resolution nanosecond spectroscopy of even-parity Rydberg excitons in Cu${}_2$O
• Nonclassical Light from Exciton Interactions in a Two-Dimensional Quantum Mirror
• Strong photon interactions from weakly interacting particles
• Purcell effect with extended sources: The role of the cross density of states
• Electro-optical properties of excitons in Cu${}_2$O quantum wells: I discrete states
• Optical to microwave frequency conversion with Rydberg excitons
• Optical properties of TiS${}_3$ as a novel thin film for single-junction and tandem solar cells
• Polarized edge state emission from topological spin phases of trapped Rydberg excitons in Cu${}_2$O
• Quantum light from lossy semiconductor Rydberg excitons
• Nonlinear optical properties and Kerr nonlinearity of Rydberg excitons in Cu${}_2$O quantum wells
• Many-Body Entanglement in Solid-State Emitters
• Renormalization of the 3D exciton spectrum by the disorder