title: Direct laser writing of near-IR step-index buried channel waveguides in rare earth doped YAG.
abstract: A new (to our knowledge) ultrashort laser pulse irradiation regime that allows us to directly modify and increase the refractive index of rare earth doped YAG polycrystalline ceramics has been identified. Single-mode buried channel waveguides in both Ho:YAG and Er:YAG ceramics at the near-IR wavelengths of 1.55 μm and 1.95 μm are demonstrated by fabricating positive square step-index cores. Minimum propagation losses of 1.5 dB cm(-1) at a 1.51 μm wavelength have been preliminarily obtained. Confocal microluminescence mapping reveals that the increased refractive index regions retain the near-IR spectral properties of Er3+ ions in the YAG crystalline matrix.
authors: School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh, UK. arodenas@gmail.com
authors: A
authors: A
authors: Rodenas
authors: A
authors: A
authors: Benayas
authors: J R
authors: JR
authors: Macdonald
authors: J
authors: J
authors: Zhang
authors: D Y
authors: DY
authors: Tang
authors: D
authors: D
authors: Jaque
authors: A K
authors: AK
authors: Kar