Abstract

High-repetition rate femtosecond lasers are shown to drive heat accumulation processes that are attractive for rapid writing of low-loss optical waveguides in transparent glasses. A novel femtosecond fiber laser system (IMRA America, FCPA µJewel) providing variable repetition rate between 0.1 and 5 MHz was used to study the relationship between heat accumulation and resulting waveguide properties in fused silica and various borosilicate glasses. Increasing repetition rate was seen to increase the waveguide diameter and decrease the waveguide loss, with waveguides written with 1-MHz repetition rate yielding ~0.2-dB/cm propagation loss in Schott AF45 glass. A finite-difference thermal diffusion model accurately tracks the waveguide diameter as cumulative heating expands the modification zone above 200-kHz repetition rate.

©2005 Optical Society of America

Waveguide writing in fused silica with a femtosecond fiber laser at 522 nm and 1 MHz repetition rate

Lawrence Shah, Alan Y. Arai, Shane M. Eaton, and Peter R. Herman
Opt. Express 13(6) 1999-2006 (2005)

Transition from thermal diffusion to heat accumulation in high repetition rate femtosecond laser writing of buried optical waveguides

Shane M. Eaton, Haibin Zhang, Mi Li Ng, Jianzhao Li, Wei-Jen Chen, Stephen Ho, and Peter R. Herman
Opt. Express 16(13) 9443-9458 (2008)

Micromachining of bulk glass with bursts of femtosecond laser pulses at variable repetition rates

Rafael R. Gattass, Loren R. Cerami, and Eric Mazur
Opt. Express 14(12) 5279-5284 (2006)

Low-loss waveguides fabricated in BK7 glass by high repetition rate femtosecond fiber laser

Shane M. Eaton, Mi Li Ng, Jörn Bonse, Alexandre Mermillod-Blondin, Haibin Zhang, Arkadi Rosenfeld, and Peter R. Herman
Appl. Opt. 47(12) 2098-2102 (2008)

Inscription and characterization of waveguides written into borosilicate glass by a high-repetition-rate femtosecond laser at 800 nm

Thomas Allsop, Mykhaylo Dubov, Vladimir Mezentsev, and Ian Bennion
Appl. Opt. 49(10) 1938-1950 (2010)