47-fs diode-pumped Yb3+:CaGdAlO4 laser

Area of Science:

• Laser Physics
• Materials Science
• Ultrafast Optics

Background:

• Femtosecond lasers are crucial for various scientific applications.
• Yb3+-doped bulk materials offer potential for efficient laser operation.
• Developing compact and high-performance ultrafast laser sources is an ongoing challenge.

Purpose of the Study:

• To experimentally demonstrate a diode-pumped passively mode-locked femtosecond laser.
• To achieve ultrashort pulse durations using an Yb3+:CaGdAlO4 single crystal.
• To investigate the performance limits of Yb3+-doped bulk material oscillators.

Main Methods:

• Direct diode pumping of an Yb3+:CaGdAlO4 single crystal oscillator.
• Passive mode-locking utilizing a semiconductor saturable-absorber mirror.
• Characterization of pulse duration, average power, and repetition rate.

Main Results:

• Generation of femtosecond laser pulses with a minimum duration of 47 fs.
• Operation at a wavelength of 1050 nm.
• Achieved average output power of 38 mW at a repetition rate of 109 MHz.
• Demonstrated the shortest laser pulses from an Yb3+-doped bulk material oscillator to date.

Conclusions:

• The Yb3+:CaGdAlO4 crystal is a suitable gain medium for high-performance femtosecond lasers.
• Diode-pumping provides an efficient and compact approach for generating ultrashort laser pulses.
• This work sets a new benchmark for pulse duration in Yb3+-doped bulk oscillators.