Photonic Systems Brown Bag Seminar

Thursday, October 28, 2004, 12 Noon                      Haus Room, 36-428

Large Area Broadband Saturable Bragg Reflectors for Femtosecond Pulse Generation

Sheila Tandon

Saturable Bragg reflectors(SBRs) can be used to self-start ultra-short pulse generation in a variety of solid state and fiber lasers.  To form shorter pulses, SBRs with broadband reflectivity are required.  In this talk, I will discuss the design and fabrication of broadband saturable Bragg reflectors through the monolithic integration of semiconductor saturable absorbers with broadband Bragg mirrors.  These SBRs have been used in a number of laser systems to achieve pulse widths on the order of 10's of femtoseconds.  The wet oxidation of AlAs creates low index AlxOy layers for broadband, high index contrast AlGaAs/Al x O y or InGaAlP/Al x O y mirrors.  Highly strained and unstrained absorbers have been stably integrated with the oxidized mirrors.  Large scale lateral oxidation techniques have enabled the fabrication of SBRs with diameters of 500 m m.  This oxidation length scale is much larger than the length scales most commonly used in vertical cavity surface emitting lasers. Large area, broadband SBRs have been used to self-start and modelock a variety of laser systems at wavelengths from 900 to 1500 nm.