Abstract: A particle detection system may include a laser optical source providing a beam of electromagnetic radiation, one or more beam shaping elements for receiving the beam of electromagnetic radiation, an optical isolator disposed in the path of the beam, between the laser source and the one or more beam shaping elements, a particle interrogation zone disposed in the path of the beam, wherein particles in the particle interrogation zone interact with the beam of electromagnetic radiation, and a first photodetector configured to detect light scattered and/or transmitted from the particle interrogation zone, a second photodetector configured to monitor power of the beam, and a controller configured to adjust the beam power based on a signal from the second photodetector, wherein the optical isolator is configured to filter optical feedback from the particle detection system out of an optical path leading to the second photodetector.

Abstract: A system, device, and method for laser cooling rare earth doped silica glass using anti-Stokes fluorescence is disclosed. The system includes a rare earth doped and codoped with one or more codopants silica glass; a laser that provides radiation to a first surface and through a body of the rare earth doped silica glass, wherein the laser is tuned from a first wavelength to a second wavelength; and a thermally sensitive device that captures images of the rare earth doped silica glass as the laser is tuned and determines a third wavelength between the first wavelength and the second wavelength where the rare earth doped silica glass is maximumly or near maximumly cooled.