Circular cladding waveguides in Pr:YAG fabricated by femtosecond laser inscription: Raman, luminescence properties and guiding performance

• Main Authors: Quanxin Yang, Hongliang Liu, Shan He, Qingyu Tian, Bin Xu, Pengfei Wu
• Format: Article
• Language: English
• Published: Institue of Optics and Electronics, Chinese Academy of Sciences 2021-03-01
• Series: Opto-Electronic Advances
• Subjects: femtosecond laser inscription; cladding waveguides; pr:yag crystal; luminescence emission
• Online Access: http://www.oejournal.org/article/doi/10.29026/oea.2021.200005
• ISSN: 2096-4579

We report on the fabrication of circular cladding waveguides with cross-section diameters of 60−120 μm in Pr:YAG crystal by applying femtosecond laser inscription. The fabricated waveguides present 2D guidance on the cross-section and fairly low propagation losses. Multiple high-order guiding modes are observed in waveguides with different diameters. Corresponding simulation results reveal the origin of a specific kind of guiding modes. Confocal micro-Raman (μ-Raman) experiments demonstrate the modification effects in femtosecond laser affected areas and ascertain the refractive index induced guiding mechanism. In addition, luminescence emission properties of Pr3+ ions at waveguide volume are well preserved during the femtosecond laser inscription process, which may result in a potential high-power visible waveguide laser.