Cryogenically cooled Fe:ZnSe-based chirped pulse amplifier at 4.07 µm
Z. Alphonse Marra, Yi Wu, Fangjie Zhou, Zenghu Chang
Abstract
A femtosecond chirped pulse amplifier based on cryogenically cooled Fe:ZnSe was demonstrated at 333 Hz—33 times higher than previous results achieved at near-room-temperature. The long upper-state lifetime allows free-running, diode-pumped Er:YAG lasers to be used as pump lasers. 250-fs, 4.59-mJ pulses are produced with a center wavelength of 4.07 µm, which avoids strong atmospheric CO 2 absorption that cuts on around 4.2 µm. It is therefore possible to operate the laser in ambient air with good beam quality. By focusing the 18-GW beam in air, harmonics up to the ninth order were observed indicating its potential for use in strong-field experimentation.
Topics & Concepts
Materials scienceOpticsLaserAmplifierFemtosecondOptoelectronicsBeam (structure)DiodeWavelengthChirped pulse amplificationHarmonicsPhysicsQuantum mechanicsVoltageCMOSLaser-Matter Interactions and ApplicationsSolid State Laser TechnologiesLaser-induced spectroscopy and plasma