The pulse duration dependence of femtosecond laser induced refractive index modulation in fused silica

With the goal of creating high refractive index modulation structures in a bulk of fused silica, we investigated the refractive index change by modulating the pulse duration of a femtosecond laser pulse. The femtosecond laser, with duration between 130 and 500 fs at a repetition rate of 1 kHz, was focused inside fused silica through a microscope objective with effective numerical aperture (NA) of 0.08. The results provided a 'triangle region', with pulse duration of 130–230 fs and pulse energy of 0.35–1.5 µJ, for the fabrication of refractive index modulation structures. The refractive index modulation structures inside fused silica were obtained only when the pulse duration was less than 230 fs under this focus condition.

[1]  A. Gaeta,et al.  Infrared photosensitivity in silica glasses exposed to femtosecond laser pulses. , 1999, Optics letters.

[2]  K. Miura,et al.  Writing waveguides in glass with a femtosecond laser. , 1996, Optics letters.

[3]  J. Nishii,et al.  In situ observation of photoinduced refractive-index changes in filaments formed in glasses by femtosecond laser pulses. , 2001, Optics letters.

[4]  Gerard Mourou,et al.  SHORT-PULSE LASER DAMAGE IN TRANSPARENT MATERIALS AS A FUNCTION OF PULSE DURATION , 1999 .

[5]  Gerard Mourou,et al.  Laser‐induced breakdown by impact ionization in SiO2 with pulse widths from 7 ns to 150 fs , 1994 .

[6]  Tsuneo Mitsuyu,et al.  Preparation and optical properties of fluoride glass waveguides induced by laser pulses , 1999 .

[7]  Nicholas F. Borrelli,et al.  Study of femtosecond-laser-written waveguides in glasses , 2002 .

[8]  J G Fujimoto,et al.  Photonic device fabrication in glass by use of nonlinear materials processing with a femtosecond laser oscillator. , 2001, Optics letters.

[9]  E. Mazur,et al.  Ultrafast-laser driven micro-explosions in transparent materials , 1997 .

[10]  H. Kogelnik.  Coupled wave theory for thick hologram gratings , 1969 .

[11]  E. Mazur,et al.  Micromachining bulk glass by use of femtosecond laser pulses with nanojoule energy. , 2001, Optics letters.

[12]  Yan Li,et al.  Holographic data storage on nonphotosensitive glass with a single femtosecond laser pulse , 2002 .

[13]  J. Nishii,et al.  Generation and recombination of defects in vitreous silica induced by irradiation with a near-infrared femtosecond laser , 2000 .

[14]  Jeremy J Baumberg,et al.  Birefringent Fresnel zone plates in silica fabricated by femtosecond laser machining. , 2002, Optics letters.

[15]  A. Streltsov,et al.  Fabrication and analysis of a directional coupler written in glass by nanojoule femtosecond laser pulses. , 2001, Optics letters.

[16]  J. Nishii,et al.  Femtosecond laser-assisted three-dimensional microfabrication in silica. , 2001, Optics letters.

[17]  Joseph S. Hayden,et al.  Waveguide fabrication in phosphate glasses using femtosecond laser pulses , 2003 .

[18]  J. Baumberg,et al.  Embedded anisotropic microreflectors by femtosecond-laser nanomachining , 2002 .

[19]  K. Hirao,et al.  Fabrication of long-period fiber gratings by focused irradiation of infrared femtosecond laser pulses. , 1999, Optics letters.

[20]  Bernard Prade,et al.  Writing of permanent birefringent microlayers in bulk fused silica with femtosecond laser pulses , 1999 .

[21]  Tsuneo Mitsuyu,et al.  Photowritten optical waveguides in various glasses with ultrashort pulse laser , 1997 .

[22]  G. Gibson,et al.  ULTRAFAST ELECTRON DYNAMICS IN FEMTOSECOND OPTICAL BREAKDOWN OF DIELECTRICS , 1999 .

[23]  J. P. Callan,et al.  Three-dimensional optical storage inside transparent materials. , 1996, Optics letters.

[24]  Koji Sugioka,et al.  Three-dimensional micro-optical components embedded in photosensitive glass by a femtosecond laser. , 2003, Optics letters.