Broadly tunable self-starting passively mode-locked Ti : sapphire laser with triple-strained quantum-well saturable Bragg reflector

Abstract

We demonstrate broadband mode-locking of femtosecond Ti:sapphire lasers with a new type of saturable Bragg reflector (SBR). Triple-strained quantum wells with separate and sequential bandgaps were used as the absorbing layer. The saturation fluence was as low as 7 mu J/cm(2). Self-starting sub-100 fs pulses tunable from 768 to 804 nm were generated in a standard X-folded cavity without intracavity tight focusing on the SBR or temperature tuning. The threshold fluence for self-starting mode-locking was 1 mu J/cm(2). (C) 1998 Elsevier Science B.V. All rights reserved.