Search results for "Continuous wave"
showing 10 items of 103 documents
Efficient and robust photo-ionization loading of beryllium ions
2017
We demonstrate the efficient generation of Be$^+$ ions with a 60 ns and 150 nJ laser pulse near 235 nm for two-step photo-ionization, proven by subsequent counting the number of ions loaded into a linear Paul trap. The bandwidth and power of the laser pulse are chosen in such a way that a first, resonant step fully saturates the entire velocity distribution of beryllium atoms effusing from a thermal oven. The second excitation step is driven by the same light field causing efficient non-resonant ionization. Our ion-loading scheme is more than 15 times more efficient as compared to former pathways using two-photon continuous wave laser excitation.
Continuous-wave backward frequency doubling in periodically poled lithium niobate
2010
We report on backward second-harmonic-generation in bulk periodically poled congruent lithium niobate with a 3.2 microns period. A tunable continuous-wave Ti:sapphire laser allowed us exciting two resonant quasi-phase-matching orders in the backward configuration. The resonances were also resolved by temperature tuning and interpolated with standard theory to extract relevant information on the sample.
Characteristics of laser operation at 1064 nm in Nd:YVO_4 under diode pumping at 808 and 914 nm
2011
International audience; A comparative study between 808 and 914nm pumping of Nd:YVO4 crystals for laser operation at 1064nm has been carried out. Using similar setups, performances of both configurations were first studied in the continuous wave, small-signal gain, and Q-switched regimes. Thanks to a numerical model, it is shown that fluorescence quenching and upconversion processes limit the possible uses for the 914nm pumping scheme to regimes with low population inversions
Continuous wave dual-wavelength operation at 1048 and 1386 nm in Nd<sup>3+</sup>:LaBGeO<inf>5</inf> for yellow laser light ge…
2007
We present results on simultaneous oscillation in continuous-wave at 1048 and 1386 nm in Nd3+:LaBGeO5 crystal. LaBGeO5 is a nonlinear positive uniaxial crystal with potential application for intracavity generation of yellow laser radiation at 597 nm. Due to the different cross section in both laser channels, simultaneous oscillation is achieved by axial hole burning in a standing wave (linear cavity). It is concluded that a stable output laser spectrum is obtained for an absorbed pump power of 700 mW. A laser competition with alternating single-channel and dual-channel oscillation at different pump regimes was observed in the experiments.
Continuous-wave, double-pass second-harmonic generation with 60% efficiency in a single MgO:PPSLT crystal
2014
We present a double-pass scheme for high-efficiency, high-power, second-harmonic generation (SHG) in a single MgO-doped periodically poled stoichiometric lithium tantalate (MgO:PPSLT) crystal. The device is pumped by a single-frequency, continuous-wave fiber amplifier laser system at a wavelength of 1091 nm. For the double-pass scheme, a conversion efficiency of 60% and a harmonic power of 12.8 W at a wavelength of 545.5 nm with a high beam quality of (M2<1.2) is achieved. Compared to single-pass SHG, a double-pass enhancement factor of more than two is observed at the highest fundamental pump power.
Continuous-wave dual-wavelength operation at 1062 and 1338nm in Nd3+:YAl3(BO3)4 and observation of yellow laser light generation at 592nm by their se…
2009
Abstract We report simultaneous oscillation in continuous wave at 1062 and 1337 nm in a Nd 3+ :YAl 3 (BO 3 ) 4 nonlinear crystal associated to the infrared laser channels 4 F 3/2 → 4 I 11/2 and 4 F 3/2 → 4 I 13/2 of Nd 3+ . Generation of yellow laser light at 592 nm produced by Type I self-sum-frequency-mixing of both fundamental infrared laser waves is observed under non-optimal phase matching conditions.
Multi-gigahertz repetition-rate-selectable passive harmonic mode locking of a fiber laser
2013
We demonstrate a passive harmonically mode-locked erbium-doped fiber laser that operates at selectable harmonics spanning from the 6th to the 928th, which corresponds to repetition rates ranging from 153 MHz to 22.2 GHz. The noteworthy laser output stability is attested by supermode suppression levels as large as 41 dB. The influence of a continuous wave background on harmonics stability is tested.
750 mW continuous-wave solid-state deep ultraviolet laser source at the 253.7 nm transition in mercury.
2007
A high-power continuous-wave coherent light source at 253.7 nm is described. It is based on a solid-state Yb:YAG disk laser with two successive frequency doubling stages and is capable of generating stable output powers of up to 750 mW. Spectroscopy of the 6 (1)S(0)-6 (3)P(1) transition of mercury has been demonstrated.
A continuous wave 10 W cryogenic fiber amplifier at 1015 nm and frequency quadrupling to 254 nm
2013
A stable, continuous wave, single frequency fiber amplifier system at 1015 nm with 10W output power is presented. It is based on a large mode double clad fiber cooled to liquid nitrogen temperature. The amplified light is frequency quadrupled to 254 nm and used for spectroscopy of the 6^1S - 6^3P transition in mercury.
Opto-thermally controlled beam steering in nonlinear all-dielectric metastructures
2021
Reconfigurable metasurfaces have recently gained a lot of attention in applications such as adaptive meta-lenses, hyperspectral imaging and optical modulation. This kind of metastructure can be obtained by an external control signal, enabling us to dynamically manipulate the electromagnetic radiation. Here, we theoretically propose an AlGaAs device to control the second harmonic generation (SHG) emission at nanoscale upon optimized optical heating. The asymmetric shape of the used meta-atom is selected to guarantee a predominant second harmonic (SH) emission towards the normal direction. The proposed structure is concurrently excited by a pump beam at a fundamental wavelength of 1540 nm and…