We report a passively mode-locked vertical external cavity surface emitting laser (VECSEL) producing 400 fs pulses with 4.35 kW peak power. The average output power was 3.3 W and the VECSEL had repetition rate of 1.67 GHz at center wavelength 1013 nm. A near-antiresonant, substrate-removed, 10 quantum well (QW) gain structure designed to enable femtosecond pulse operation is used. SESAM which uses fast carrier recombination semiconductor optical Stark effect enables passive mode-locking....

Surface-emitting semiconductor lasers can make use of external cavities and optical pumping techniques to achieve a combination high continuous-wave output power near-diffraction-limited beam quality that is not matched by any other type source.The ready access the laser mode cavity provides has been exploited for applications such as intra-cavity frequency doubling passive mode-locking.The purpose this Topical Review outline operating principles these versatile summarize capabilities...

Picosecond pulses at gigahertz repetition rates from two different passively mode-locked VECSELs are amplified to high powers in cascaded ytterbium doped fiber amplifiers.Small differences pulse durations between the led amplification nonlinear regimes.The shorter 0.5 ps could be 53 W of average power parabolic regime.This was confirmed by excellent compression down 110 fs.The VECSEL producing longer 4.6 an SPM dominated regime up 200 but with poor recompressed quality.

In 1832 Hamilton predicted conical refraction, concluding that if a beam propagates along an optic axis of biaxial crystal, hollow cone light will emerge. Nearly two centuries on, cascade refraction involving multiple crystals has not been investigated. We empirically investigate unique two-crystal configuration, and use this to demonstrate ultra-efficient Nd:KGd(WO(4))(2) laser providing multi-watt output with excellent quality independent resonator design slope efficiency close the...

We report on 260 fs transform-limited pulses generated directly by an optical Stark passively mode-locked semiconductor disk laser at a 1 GHz repetition rate. A surface recombination saturable absorber mirror and step-index gain structure are used. Numerical propagation modeling of the effect confirms that this mechanism is able to form we observe.

We report a passively mode-locked vertical-external-cavity surface-emitting laser (VECSEL) producing 335-fs near-transform-limited pulses at repetition rate of 1 GHz with an average output power 120 mW center wavelength 999 nm. The VECSEL was optically pumped 1.85 W 830 peak the 315 W.

Abstract The authors of the recent paper titled “SESAM‐free mode‐locked semiconductor disk laser” [1] make claim that Kerr lens mode‐locking has been observed in a SESAM free laser. However, data presented manuscript at best weakly support central this laser is and worst are simply characterisation continuous‐wave (CW) physical principles clearly defined many text books as well first reporting [2] more recently work H. A. Haus [3]. When new technique for particular class laser, it essential...

We report a harmonically mode-locked vertical external cavity surface emitting laser (VECSEL) producing 400 fs pulses at repetition frequency of 175 GHz with an average output power 300 mW.Harmonic mode-locking was established using µm thick intracavity single crystal diamond heat spreader in thermal contact the front gain sample liquid capillary bonding.The set by microcavity and stable harmonic mode locking achieved when length tuned so that operated on 117th fundamental cavity.When etalon...

We measure the nonlinear refractive index of an antiresonant 1050 nm semiconductor disk laser (SDL) gain medium using a reflection-type z-scan system, with 1064 nm, 10-ps-pulse as probe, and fiber-coupled 808 diode pump for carrier injection. Empirically, is found to depend approximately linearly on applied intensity, having value −1.5(0.2) × 10−12 cm2/W at zero excitation but increasing take positive values typical SDL operating conditions. The focal lengths corresponding Kerr lenses...

We demonstrate multiwatt cw output power from an optically pumped quantum-dot semiconductor disk laser. Continuous-wave of 4.35 W with 22% slope efficiency was demonstrated at a center wavelength 1032 nm. This represents increase in 15 times and 10 the previously published results using Stranski–Krastanow grown quantum dots. An intracavity diamond heat spreader used for thermal management. The maximum limited by available pump power, no sign rollover observed.

We report on supercontinuum generation using a mode-locked VECSEL emitting 400-fs pulses at 3-GHz repetition rate, amplified with cascaded ytterbium-doped fiber amplifier system up to 40 W of average power. The are then recompressed their original duration via high throughput transmission grating compressor, and used generate in two samples photonic crystal (PCF): an all-normal dispersion PCF, PCF zero wavelength 1040 nm, creating 20 dB spectral bandwidths 200 nm 280 respectively.

We report a distributed Bragg reflector‐free semiconductor disc laser which emits 10 W continuous wave output power at wavelength of 1007 nm when pumped with 40 808 nm, focused into 230 μm diameter spot on the gain chip. By introducing birefringent filter plate in cavity could be tuned from 995 to 1020 nm. The consisted chip located beam waist linear concentric resonator an coupling 2.15%. consists 1.574‐μm‐thick resonant periodic structure, ten In 0.13 Ga 0.87 As quantum wells embedded...

We report what we believe to be the first demonstration of an all-semiconductor room-temperature terahertz time domain spectrometer. An optical Stark mode-locked vertical-external-cavity surface-emitting laser with 480 fs pulses at 1044 nm was used illuminate low-temperature-grown photoconductive antennae 5 mum-gap bow-tie-shaped electrodes. The coherently detected spectrum has a bandwidth close 1 THz, in which water absorption lines 0.555 and 0.751 THz can resolved.

We report a solar pumped solid state laser using 20 mm long, 3 diameter neodymium-doped yttrium aluminum garnet rod. This rod was placed in liquid cooling chamber water-white-emulsion-paint mix. mix provides for the crystal and also doubles as diffuse light scattering liquid. enhances sunlight leads to greater absorption numerically model ray-tracing predict 2.6 times enhancement when 98% reflective scatter is modelled compared 0% scattering. experimentally demonstrated this, showing 2.58...

An optical Stark modelocked vertical-external-cavity surface-emitting laser producing sub-500 fs pulses at a fundamental repetition rate of 1 GHz was actively stabilised by locking its output to 10 MHz electrical oscillator using programmable phase-locked-loop frequency synthesiser. The timing jitter characterised the von der Linde method and found be 190(12) in bandwidth 300 Hz 1.5 MHz.

We report the generation of subpicosecond pulses from a passively mode locked, optically pumped quantum well semiconductor disk laser using dot saturable absorber mirror (SESAM). obtained 870 fs at repetition rate 895 MHz with average output power 45 mW 1027.5 nm. The locking operation was insensitive to SESAM temperature over range −10 85 °C, pulse duration variation thought be dominated by dependence group delay dispersion.

Coupled-cavity passive harmonic mode-locking of a quantum well based vertical-external-cavity surface-emitting laser has been demonstrated, yielding an output pulse train 1.5 ps pulses at repetition rate 80 GHz and with average power mW. Harmonic results from coupling between the main cavity formed within substrate saturable absorber structure. Mode-locking on second allows 1.1 to be generated 147 40 mW power.

We present a method to experimentally characterize the gain filter and calculate corresponding parabolic bandwidth of lasers that are described by "class A" dynamics solving master equation spectral condensation for Gaussian spectra. determine filter, with an equivalent up 51 nm, broad-band InGaAs/GaAs quantum well surface-emitting semiconductor laser structures capable producing pulses down 60 fs width when mode-locked optical Stark saturable absorber mirror.

We report a repetition frequency tunable, passively mode-locked vertical-external-cavity surface-emitting semiconductor laser (VECSEL) with continuous tuning between 2.78 and 7.87 GHz using mechanical of the cavity length. The emits near-transform-limited, sub-500-fs pulses over almost an octave range 5 GHz. At rates above 6 pulse duration increases to ~2.5 ps. Over entire average output power 40 ± mW in fundamental transverse mode. change highlights dominant modelocking mechanism which...

The timing jitter of 2.3 ps 1043 nm pulses from a passively modelocked surface-emitting semiconductor laser has been characterised. vertical external cavity was stabilised by locking the pulse repetition rate to an electronic oscillator at ∼897 MHz. Jitter measured be 160(30) fs over bandwidth 1 kHz 15

Terahertz (THz) radiation can be generated by ultrafast photo-excitation of carriers in a semiconductor partly masked gold surface. A simulation the effect taking into account diffusion and electric field shows that total net current is approximately zero cannot for THz radiation. Finite element modelling analytic calculations indicate emission arises because metal inhibits from part dipole population, thus creating an asymmetry therefore current. Experimental investigations confirm...

We report a femtosecond-pulse vertical-external-cavity surface-emitting laser with continuous repetition frequency tuning range of 8% near 1 GHz. A constant average output power 56 ± mW and near-transform-limited pulse duration 450 20 fs were observed across the entire range.