High energy mode-locked Yb-doped fiber laser with Bi2Te3 deposited on tapered-fiber

The report presents the high energy mode-locking operation in an all-normal-dispersion Yb-doped mode-locked fiber laser based on evanescent field interaction with tapered fiber deposited with Bi2Te3 topological insulator. Different from most of solution processing methods, Bi2Te3 film is deposited on the tapered fiber by pulsed laser deposition (PLD) technology. In this way, it can bring less non-saturable losses and contact to the fiber better. By incorporating this novel fiber-taper Bi2Te3 saturable absorber into Yb-doped fiber laser cavity, a repetition rate of 6.2 MHz mode-locked fiber laser is achieved. The maximum single pulse energy of 2 nJ is obtained. The results indicate that fiber-taper Bi2Te3 saturable absorber possesses potentiality for high power mode-locked fiber laser applications.