Deep ultraviolet spontaneous emission enhanced by layer dependent black phosphorus plasmonics

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanophotonics

Background:

• Graphene's isotropic optical properties limit spontaneous emission engineering.
• Black Phosphorus (BP) exhibits in-plane anisotropic and thickness-dependent optical properties.
• Anisotropy and thickness offer additional control over plasmonic modes and light-matter interactions.

Purpose of the Study:

• Investigate the effects of black phosphorus (BP) anisotropy and thickness on spontaneous emission from a Hydrogenic emitter.
• Explore the tunability of the Purcell factor (PF) by varying BP thickness, emitter orientation, and doping levels.

Main Methods:

• Theoretical investigation of spontaneous emission rates.
• Analysis of plasmonic modes supported by BP.
• Modeling the influence of BP thickness and emitter orientation on the Purcell factor.

Main Results:

• The Purcell factor (PF) is dependent on emitter orientation and BP thickness.
• Increasing BP thickness enhances the PF at lower frequencies due to infrared (IR) plasmons, boosting visible and UV emission.
• Deep UV emission (103 nm or 122 nm) can be switched by controlling thickness and distance.
• Doping significantly tunes the PF near BP, with alterations dependent on BP thickness.

Conclusions:

• Black Phosphorus is a promising material for controlling light-matter interactions via the Purcell effect.
• Tunability is achieved through variations in doping, emitter orientation, and BP thickness.
• BP offers a versatile platform for advanced photonic applications requiring precise control over spontaneous emission.