Photoluminescent cooling of 10% Yb:YLF with light emitting diodes

In recent decades, photoluminescent cooling has emerged as a promising route toward achieving solid-state cooling without mechanical components or refrigerants. The underlying principle involves the anti-Stokes fluorescence process, in which a material absorbs lower-energy photons and re-emits photons of higher energy, effectively removing thermal energy from the solid lattice. While this phenomenon has been primarily studied using coherent, laser-based excitation sources, recent interest has turned toward exploring whether similar cooling mechanisms can occur under incoherent light. This project investigates optical refrigeration of ytterbium-doped lithium yttrium fluoride (Yb:YLF) using infrared LEDs as an alternative to traditional laser cooling. If realized, it could enable passive, low-maintenance cooling systems suitable for electronics, sensors, and optical components.