Photosensitivity in phosphate glass doped with Ag+ upon exposure to near-ultraviolet femtosecond laser pulses

We report on a photosensitivity in soda-alumino-phosphate glass doped with silver ions Ag+ upon exposure to near-ultraviolet femtosecond laser pulses. The photosensitivity, i.e., formation of color centers such as Ag0 and Ag2+ in the glass is found to be associated with intensity-dependent nonlinear optical process induced by extremely high irradiance up to ∼TW/cm2 of the femtosecond pulses. We demonstrate a bright orange fluorescence from the induced color centers inside the glass, that should be applicable to a functional optical device.