Université de Neuchâtel

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

Labaye, François ; Gaponenko, Maxim ; Modsching, Norbert ; Brochard, Pierre ; Paradis, Clément ; Schilt, Stéphane ; Wittwer, Valentin Johannes ; Südmeyer, Thomas

In: IEEE Journal of Selected Topics in Quantum Electronics, 2019, vol. 25, no. 4, p. # 8800619

Ultrafast thin-disk laser (TDL) oscillators provide higher intracavity pulse energy, average power, and peak power levels than any other femtosecond laser oscillator technology. They are suitable for driving extreme nonlinear interactions directly inside the laser oscillator. High harmonic generation (HHG) driven inside ultrafast TDL oscillators is a very recent approach for the generation of...

Public access from Jun 1, 2020
Université de Neuchâtel

10 kHz linewidth mid-infrared quantum cascade laser by stabilization to an optical delay line

Shehzad, Atif ; Brochard, Pierre ; Matthey, Renaud ; Südmeyer, Thomas ; Schilt, Stéphane

In: Optics Letters, 2019, vol. 44, no. 4, p. 3470-3473

We present a mid-infrared quantum cascade laser (QCL) with a sub-10 kHz full width at half-maximum linewidth (at 1 s integration time) achieved by stabilization to a free-space optical delay line. The linear range in the center of a fringe detected at the output of an imbalanced Mach–Zehnder interferometer implemented with a short free-space pathlength difference of only 1 m is used as a...

Université de Neuchâtel

Carrier-envelope offset frequency stabilization of a thin-disk laser oscillator operating in the strongly self-phase modulation broadened regime

Modsching, Norbert ; Paradis, Clément ; Brochard, Pierre ; Jornod, Nayara ; Gürel, Kutan ; Kränkel, Christian ; Schilt, Stéphane ; Wittwer, Valentin J ; Südmeyer, Thomas

In: Optics Express, 2018, vol. 26, no. 22, p. 28461-28468

We demonstrate the carrier-envelope offset (CEO) frequency stabilization of a Kerr lens mode-locked Yb:Lu2O3 thin-disk laser oscillator operating in the strongly self-phase modulation (SPM) broadened regime. This novel approach allows overcoming the intrinsic gain bandwidth limit and is suited to support frequency combs from sub-100-fs pulse trains with very high output...

Université de Neuchâtel

Ultra-low noise microwave generation with a free-running optical frequency comb transfer oscillator

Brochard, Pierre ; Schilt, Stéphane ; Südmeyer, Thomas

In: Optics Letters, 2018, vol. 43, no. 19, p. 4651-4654

We present ultra-low noise microwave synthesis by optical to radio-frequency (RF) division realized with a free-running or RF-locked optical frequency comb (OFC) acting as a transfer oscillator. The method does not require any optical lock of the OFC and circumvents the need for a high-bandwidth actuator. Instead, the OFC phase noise is electrically removed from a beat-note signal with an optical...

Université de Neuchâtel

Electrically-driven pure amplitude and frequency modulation in a quantum cascade laser

Shehzad, Atif ; Brochard, Pierre ; Matthey, Renaud ; Blaser, Stéphane ; Gresch, Tobias ; Maulini, Richard ; Muller, Antoine ; Südmeyer, Thomas ; Schilt, Stéphane

In: Optics Express, 2018, vol. 26, no. 9, p. 12306-12317

We present pure amplitude modulation (AM) and frequency modulation (FM) achieved electrically in a quantum cascade laser (QCL) equipped with an integrated resistive heater (IH). The QCL output power scales linearly with the current applied to the active region (AR), but decreases with the IH current, while the emission frequency decreases with both currents. Hence, a simultaneous modulation...

Université de Neuchâtel

Frequency Noise Characterization of a 25-GHz Diode-Pumped Mode-Locked Laser With Indirect Carrier-Envelope Offset Noise Assessment

Brochard, Pierre ; Wittwer, Valentin Johannes ; Bilicki, Slawomir ; Resan, Bojan ; Weingarten, Kurt John ; Schilt, Stéphane ; Südmeyer, Thomas

In: IEEE Photonics Journal, 2018, vol. 10, no. 1, p. # 3200110

We present a detailed frequency noise characterization of an ultrafast diode-pumped solid-state laser operating at 25-GHz repetition rate. The laser is based on the gain material Er:Yb:glass and operates at a wavelength of 1.55 μm. Using a beating measure-ment with an ultralow-noise continuous-wave laser in combination with a dedicated electrical scheme, we measured the frequency noise...

Université de Neuchâtel

Carrier-envelope offset frequency stabilization of a gigahertz semiconductor disk laser

Jornod, Nayara ; Gürel, Kutan ; Wittwer, Valentin J ; Brochard, Pierre ; Hakobyan, Sargis ; Schilt, Stéphane ; Waldburger, Dominik ; Keller, Ursula ; Südmeyer, Thomas

In: Optica, 2017, vol. 4, no. 12, p. 1482-1487

Optical frequency combs based on ultrafast lasers have enabled numerous scientific breakthroughs. However, their use for commercial applications is limited by the complexity and cost of femtosecond laser technology. Ultrafast semiconductor lasers might change this issue as they can be mass produced in a cost-efficient way while providing large spectral coverage from a single technology. However,...

Université de Neuchâtel

Power Spectrum Computation for an Arbitrary Phase Noise Using Middleton’s Convolution Series : Implementation Guideline and Experimental Illustration

Brochard, Pierre ; Südmeyer, Thomas ; Schilt, Stéphane

In: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2017, vol. 64, no. 11, p. 1766-1775

In this paper, we revisit the convolution series initially introduced by Middleton several decades ago to determine the power spectrum (or spectral line shape) of a periodic signal from its phase noise power spectral density. This topic is of wide interest, as it has an important impact on many scientific areas that involve lasers and oscillators. We introduce a simple guideline that enables a...

Université de Neuchâtel

Full stabilization and characterization of an optical frequency comb from a diode-pumped solid-state laser with GHz repetition rate

Hakobyan, Sargis ; Wittwer, Valentin J ; Brochard, Pierre ; Gürel, Kutan ; Schilt, Stéphane ; Mayer, Aline S ; Keller, Ursula ; Südmeyer, Thomas

In: Optics Express, 2017, vol. 25, no. 17, p. 20437-20453

We demonstrate the first self-referenced full stabilization of a diode-pumped solid-state laser (DPSSL) frequency comb with a GHz repetition rate. The Yb:CALGO DPSSL delivers an average output power of up to 2.1 W with a typical pulse duration of 96 fs and a center wavelength of 1055 nm. A carrier-envelope offset (CEO) beat with a signal-to-noise ratio of 40 dB (in 10-kHz resolution bandwidth) is...

Université de Neuchâtel

Rb-stabilized laser at 1572 nm for CO2 monitoring

Matthey, Renaud ; Moreno, William ; Gruet, Florian ; Brochard, Pierre ; Schilt, Stéphane ; Mileti, Gaetano

In: Journal of Physics: Conference Series, 2016, vol. 723, no. 1, p. 012034

We have developed a compact rubidium-stabilized laser system to serve as optical frequency reference in the 1.55-μm wavelength region, in particular for CO2 monitoring at 1572 nm. The light of a fiber-pigtailed distributed feedback (DFB) laser emitting at 1560 nm is frequency-doubled and locked to a sub-Doppler rubidium transition at 780 nm using a 2-cm long vapor glass cell. Part of...