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In this article we demonstrate the first, to the best of our knowledge, all-fiber self-starting laser oscillator consisting entirely of polarization-maintaining large mode area (PLMA) fibers mode-locked with nonlinear optical loop mirror (NOLM). The system works in a Raman-free dissipative soliton regime and operates at a central wavelength of 1030 nm. It delivers stable ultrashort pulses of high energy of 12 nJ at a 7.56 MHz repetition rate which can be compressed down to the Fourier transform limit of ~250 fs. Higher energies were limited by the formation of multiple pulses in the cavity.

We report on a single-frequency Tm-doped fiber laser based on a high-quality (Q) prolate microresonator. A maximum power of 0.9 W was extracted from the laser oscillator directly. To our best knowledge, it is the first report on a Watt-level single-frequency laser at the 2- $\mu \text{m}$ wavelength band with such a laser configuration. The laser linewidth is measured to be ~15.1 kHz by self-heterodyne method. Moreover, we explore the tuning ability of the laser through exciting different modes in the microresonator selectively. A wavelength-tuning range of 20 nm is obtained. The approach can be a competitive candidate for developing tunable, highly efficient, and high-power single-frequency lasers in the 2- $\mu \text{m}$ band.

In this work we report on the output performances of a Nd:YVO4 picosecond (ps) laser oscillator that was passively modulated by different semiconductor saturable absorber mirrors (SESAMs). The laser emission characteristics are given for SESAM used in Z-type and W-type cavities under similar pumping conditions. Q-switch mode-locking (QML) regime was obtained in the Z-type resonator whereas the W-type oscillator enabled stable mode-locking (ML) operation. For the W-type cavity ML performances are reported for two SESAMs with distinct parameters. Thus the use of a SESAM with 10 ps long recovery time allowed ML operation with pulses of 11.1 nJ energy and 15 ps duration (0.74 kW peak power) at 158 MHz repetition rate; the average power at 1.06 μm was 1.75 W for 5.17 W pump power at 809 nm. Employing a second SESAM with 0.5 ps short recovery time, the Nd:YVO4 laser yielded pulses with increased 13.4 nJ pulse energy and shorter, 12.5 ps, duration (1.1 kW peak power) at 158 MHz repetition rate, corresponding to 2.11 W average power; the pump power was 5.09 W. The results highlight the significant role of the SESAM parameters as well as of the implemented cavity design for the construction of a ps laser source of high performance.

In this work, we present an all-polarization-maintaining, all-large-mode-area fiber laser oscillator passively mode-locked using a nonlinear optical loop mirror. The ytterbium-doped system, working in a Raman-free regime, operates at a central wavelength of 1.03 μ;m. The oscillator emits 12 nJ pulses at a repetition rate of 7.56 MHz. Positively chirped pulses from an all-normal-dispersion cavity can be externally compressed to the duration of 250 fs.

By exploiting the anisotropic radiation pattern of an elementary dipole in a laser material, we report a gain enhancement factor of 1.3104 for an off-axis Raman laser in a monolithic y-cut versus z-cut KTP crystal.

A novel pumping approach for Yb-doped gain materials enables a Kerr-lens mode-locked Yb-CALGO laser to overcome previous bandwidth limitations and to generate 22-fs pulses with an average power of 729 mW and 25% optical-to-optical efficiency.

Operating in a regime of strong self-phase-modulation, 84-fs pulses are generated with 42-MW peak power and 12% efficiency from Yb:YAG. We demonstrate a 3x higher average power than any previous sub-100-fs laser oscillator.

As self-sustained oscillators, lasers possess the unusual ability to spontaneously synchronize. These nonlinear dynamics are the basis for a simple yet powerful stabilization technique known as injection locking, in which a laser's frequency and phase can be controlled by an injected signal. Due to its inherent simplicity and favorable noise characteristics, injection locking has become a workhorse for coherent amplification and high-fidelity signal synthesis in applications ranging from precision atomic spectroscopy to distributed sensing. Within integrated photonics, however, these injection locking dynamics remain relatively untapped--despite significant potential for technological and scientific impact. Here, we demonstrate injection locking in a silicon photonic Brillouin laser for the first time. Injection locking of this monolithic device is remarkably robust, allowing us to tune the laser emission by a significant fraction of the Brillouin gain bandwidth. Harnessing these dynamics, we demonstrate amplification of small signals by more than 23 dB. Moreover, we demonstrate that the injection locking dynamics of this system are inherently nonreciprocal, yielding unidirectional control and back-scatter immunity in an all-silicon system. This device physics opens the door to new strategies for phase noise reduction, low-noise amplification, and back-scatter immunity in silicon photonics., Comment: 15 pages

We report a Kerr lens mode-locked ring thin-disk oscillator with an output power of 24.7 W with the highest demonstrated repetition rate of 120.7 MHz. © 2020 The Author(s)

A low-volume mode-locked oscillator has been designed for environmental robustness and is suitable for frequency comb applications. Performance metrics include signal-to-noise ratios greater than 40 dB and in-loop Allan Deviations below 1 x 10-16/Vr.

We present the first dual-comb thin-disk laser based on polarization splitting. It generates 6-W and 8-W outputs of 240-fs pulses with adjustable repetition rate. We investigate noise properties and demonstrate a proof-of-principle spectroscopy experiment.

International audience; Summary form only given. VIRGO is a 3-km-arm laser interferometer for gravitational wave detection in the 20 Hz-5 kHz frequency band. Its second-generation version, Advanced VIRGO, aims at reducing the detector noise by a factor of ten compared to the first generation, with the progressive deployment of new technologies and equipment [1]. The first detections of gravitational waves with VIRGO were made in August 2017 [2]. For its next scientific observations with an increased sensitivity, a pre-stabilized laser system twice as powerful has been developed. It comprises a new 100-W solid-state amplifier pumped at 878.7 nm. It is the first time such amplifier is integrated in a gravitational wave detector, LIGO detectors using a 70 W amplifier pumped at 808 nm. Power noise, long term power stability, frequency noise, beam jitter and transverse mode quality have been extensively studied and compared to Advanced VIRGO requirements. The pre-stabilized laser system, emitting a continuous wave at 1064 nm, is based on a 17 W laser oscillator, injection locked onto a low frequency noise 500 mW source, followed by the new 100 W amplifier and a 1.6-mperimetre bow -tie shape Fabry-Perot cavity acting as a spatial and temporal mode cleaner. The optical amplifier, manufactured by neoLASE, is based on four Nd3+:YVO4crystals pumped longitudinally each with 50 W at 878,7 nm coming from volume Bragg grating diode lasers. The pump light is transported by 20 meters of multi mode fi bers deployed between two separate rooms for acoustic and electromagnetic contamination reasons. The fi rst test and characterization campaign was performed in Nice in 2017 followed by the integration at the VIRGO site. The system has been working continuously for commissioning for more than one year. The amplifier delivers 96 W with 17 W input and reaches 100 W with increased input power. No global decrease of the amplifier output power has been so far observed. The relative intensity noise spectrum (Fig. 1-a) is below 10 -4 x(10 Hz/f) 1 / 2 Hz -1 / 2 in the detection band and limited by 13 mA photocurrent shot noise (5x 10 Hz 1/2 ) in the 5-10 MHz band used for modulation. Further power noise reduction is realized by combining passive fi ltering from Fabry-Perot mode cleaners and active power stabilization with an acousto-optic modulator in transmission to reach 2x 10 -9 Hz -1 / 2 in the detector band. The spectrum of the frequency noise added by the amplifier (Fig. 1-b) was measured with a heterodyne interferometer and is lower than 3x 10 -1 Hz/Hz 1 / 2 , far below the master laser oscillator. Those performances are compliant with Advanced VIRGO specifications [1].

Titanium-doped sapphire (Ti:Al 2 O 3 ) is a gain medium with a very broad emission bandwidth allowing the generation and amplification of very short pulses (<

A diode-side-pumped laser oscillator with a Tm,Ho:YLF rod conductively cooled to −80 °C was developed. A Q-switched pulse energy of 104 mJ was achieved at a pulse repetition frequency of 70 Hz, corresponding to an average output power of 7.28 W. In addition, the maximum Q-switched pulse energy of 125 mJ was obtained at 50 Hz. Even at the maximum output level, the beam quality factor $M^{\mathrm {\mathbf {2}}}$ was measured to be $\leq $ 1.5. To the best of our knowledge, this is the highest average output power reported for a 100-mJ-class Q-switched 2- $\mu \text{m}$ laser oscillator using a conductively cooled laser head.

A 500 kHz burst-mode YVO4/Nd:YVO41064 nm laser oscillator with a burst duration of 1 ms and a burst energy of 45.0 mJ was presented. The acousto-optically Q-switched frequency could be varied from 10 kHz to 500 kHz, resulting in 10–500 sub-pulses per burst. At the pulse repetition rate of 500 kHz, the maximum single pulse energy reached 90.0 μJ with a pulse width of 37.8 ns, corresponding to a peak power of 2.4 kW. The beam quality factor of burst-mode laser at 500 kHz was measured to be M2=1.6. The burst-mode YVO4/Nd:YVO4laser could be acted as a master oscillator for further power scaling.

We have successfully applied intermode beating mode-locking (IBML) for short pulse generation in compact Tm3+-doped double clad fiber lasers (TDFLs). This IBML technique is implemented by longitudinal-mode frequency matching between pump source and laser oscillator without extra mode-locker. Here, the achieved IBML TDFLs can respectively generate 2056.47 nm, 2003.88 nm and 1963.79 nm short pulses. Their output characteristics have been respectively investigated. The IBML technique enables the large pulse energy of ~20.8 nJ with pulse repetition rate of ~9.6 MHz. This work may open a new route for next-generation of high performance mid-infrared short-pulse all-fiber laser sources.

A cladding-pumped Tm fibre is designed and fabricated with a ring-structured fibre core geometry, optimised for power-scalable, single-mode 1907 nm operation with 67.0% slope efficiency and demonstrated in an all-fibre laser oscillator configuration.

We demonstrate a Kerr lens mode-locked thin-disk laser oscillator operating with 95-fs pulses at 21.1 W of average power. This is the highest average power achieved by any oscillator in the sub-100-fs regime.

The first chapter has pointed out important breakthroughs of solid-state laser architectures. In particular Ti:sapph lasers have revolutionized frequency metrology and ultrafast optics. The introduction has also emphasized the potential of the thin-disk technology to become the foundation of the upcoming power-scalable laser oscillator generation.

We present a 350-W 940-fs thin-disk oscillator. We achieve this new record-high average power ultrafast oscillator through vacuum operation, multiple passes on the disk, and large pump spot. Systematic power-scaling through multi-pass cavities is discussed.

We demonstrate antenna-coupled spintronic terahertz (THz) emitters excited by 1550 nm, 90 fs laser pulses. Antennas are employed to optimize THz outcoupling and frequency coverage of ferromagnetic/nonmagnetic metallic spintronic structures. We directly compare the antenna-coupled devices to those without antennas. Using a 200 μm H-dipole antenna and an ErAs:InGaAs photoconductive receiver, we obtain a 2.42-fold larger THz peak-peak signal, a bandwidth of 4.5 THz, and an increase in the peak dynamic range (DNR) from 53 dB to 65 dB. A 25 μm slotline antenna offered 5 dB larger peak DNR and a bandwidth of 5 THz. For all measurements, we use a comparatively low laser power of 45 mW from a commercial fiber-coupled system that is frequently employed in table-top THz time-domain systems.We demonstrate antenna-coupled spintronic terahertz (THz) emitters excited by 1550 nm, 90 fs laser pulses. Antennas are employed to optimize THz outcoupling and frequency coverage of ferromagnetic/nonmagnetic metallic spintronic structures. We directly compare the antenna-coupled devices to those without antennas. Using a 200 μm H-dipole antenna and an ErAs:InGaAs photoconductive receiver, we obtain a 2.42-fold larger THz peak-peak signal, a bandwidth of 4.5 THz, and an increase in the peak dynamic range (DNR) from 53 dB to 65 dB. A 25 μm slotline antenna offered 5 dB larger peak DNR and a bandwidth of 5 THz. For all measurements, we use a comparatively low laser power of 45 mW from a commercial fiber-coupled system that is frequently employed in table-top THz time-domain systems.