Kerr lens mode-locked Yb:CALGO thin-disk laser

Abstract

We demonstrate the first Kerr lens mode-locked Yb:CaGdAlO (Yb:CALGO) thin-disk laser oscillator. It generates pulses with a duration of 30 fs at a central wavelength of 1048 nm and a repetition rate of 124 MHz. The laser emits the shortest pulses generated by a thin-disk laser oscillator, equal to the shortest pulse duration obtained by Yb-doped bulk oscillators. The average output power is currently limited to 150 mW by the low gain and limited disk quality. We expect that more suitable Yb:CALGO disks will enable substantially higher power levels with similar pulse durations.

XUV Sources Based on Intra-Oscillator High Harmonic Generation With Thin-Disk Lasers: Current Status and Prospects

“…Nowadays, such lasers have achieved an intracavity peak power of 1.76 GW [78], which is almost an order of magnitude higher than values obtained with SESAM-mode-locked TDL oscillators [56]. Furthermore, KLM TDL oscillators can generate pulses with durations down to 30 fs, which is the shortest value ever achieved with a mode-locked TDL oscillator [81]. These two results already show that KLM TDL oscillators can achieve sufficiently large intracavity peak power and short pulses duration for efficient HHG.…”

“…10, could allow for a mitigation of the gain reduction between cw and mode-locked operation. However, while this gain material achieved the shortest pulses from TDL oscillators for both SESAM-mode-locked [90] and KLM [81] operation, sub-150-fs Yb:CALGO-based TDL oscillators have not shown intracavity peak power above a few tens of megawatts.…”

“…Today, intracavity peak powers in the order of multi-hundreds of MW have been obtained with sub-150-fs pulses [57]. Pulse durations as short as 30 fs were demonstrated [81] from diodepumped Yb-doped gain materials. This performance makes TDL oscillators ideal candidates for applications of intra-oscillator extreme nonlinear optics and a suitable base for the development of high-flux table-top XUV light sources at megahertz repetition rates based on HHG.…”

Compact laser sources from the extreme ultraviolet to the mid-infrared spectral range

“…Nowadays, Yb:CALGO still holds the short pulse duration record of SESAM-modelocked TDLs [111] (49 fs with 2 W of average power, presented in section 3.2.1), as well as the shared record of any Yb-doped modelocked solid-state laser (including bulk lasers) with an Yb:CaYAlO4 bulk oscillator [112] (30 fs with 15 mW of average power) and a Kerr-lens modelocked CALGO bulk oscillator [113] (32 fs with 90 mW of average power). Indeed, the first demonstration of a Kerr-lens modelocked CALGO TDL realized in at the LTF at the University of Neuchâtel equalized this values [98] with even slightly higher average power (30 fs with 150 mW of average power).…”

“…Intracavity peak powers up to 1.76 GW have been generated [96]. Recently, ultrafast TDL oscillators based on Yb-doped gain materials achieved pulse durations as short as 30-fs directly emitted from the oscillator [97,98]. Furthermore, they can operate with low noise and carrier-envelope offset (CEO) frequency stabilization has been achieved [99][100][101][102], showing their suitability for frequency comb applications.…”