Carrier‐Envelope‐Offset Frequency Stable 100 W‐Level Femtosecond Thin‐Disk Oscillator

Abstract

In this paper, the carrier‐envelope‐offset (CEO) frequency stabilization of a Kerr‐lens mode‐locked femtosecond oscillator with average power 105 W is presented. Intra‐cavity Kerr lensing is realized in a quartz crystal that simultaneously serves as an acousto‐optic loss modulator. This novel method results in a CEO frequency stable laser with high average power and a residual in‐loop phase noise below 90 mrad. Furthermore, an all‐solid‐state bulk broadening stage is presented. The compressed, CEO frequency‐stabilized output has a peak power exceeding 67 MW at a pulse duration of 40 fs and a repetition rate of 15.6 MHz. The intra‐cavity peak power of the CEO frequency‐stabilized oscillator is around 200 MW. These results pave the way toward compact, transportable all‐solid‐state drivers with high repetition rates for deep UV and XUV frequency combs and other nonlinear processes.

Carrier-Envelope Offset Frequency Stabilization of a Thin-Disk Laser Oscillator via Depletion Modulation

“…Similar peaks can also be observed in the stabilized CEO signal in Ref. [16], and although harmonics are barely distinguishable in the results reported in [3], [15], there is a pronounced contribution to the integrated phase noise at ∼7 kHz. We did not investigate the origin of these noise peaks, however it was previously suggested that they might arise from the power supply of the pump diode, as they are clearly visible in its relative intensity noise [11].…”

“…Another demonstrated method for CEO stabilization of TDLs employs an acousto-optic modulator (AOM) in the oscillator [3], [16] enabling a direct modulation of the intracavity losses. This scheme proved to be power-scalable and allowed the realization of a tight CEO lock due to a large locking bandwidth of 230 kHz.…”

“…This scheme proved to be power-scalable and allowed the realization of a tight CEO lock due to a large locking bandwidth of 230 kHz. In the work of Gröbmeyer et al [16], the AOM was used as the Kerr-lens element of the TDL and the laser output power exceeded 100 W. However, a special AOM was needed, and with the advent of more sophisticated designs for high-power TDLs [17], the inclusion of an intracavity AOM might be hindered in the future.…”

“…Lastly, worthy of consideration for the stabilization of TDLs is the use of a semiconductor saturable absorber mirror (SESAM) as an opto-optical modulator [18]. Other methods for f CEO locking in the case of high-power TDLs have been discussed elsewhere [16].…”

The amazing progress of high-power ultrafast thin-disk lasers

“…In parallel to these efforts, large progress has been made in finding paths for efficient external pulse compression of these high-average power laser systems using hollow-core fibers [48], multi-pass cells [49][50][51][52], hybrid setups including multi-plate compressors [53], and even spectral broadening in the amplifier itself [54] bringing these applications one step closer. Additionally, as the pulse durations from these systems keeps getting shorter and approach the few-cycle regime, carrier-envelope phase control becomes increasingly relevant, in particular for high-power oscillators which can be used as powerful seeds for booster amplifiers [55,56].…”