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Highly transparent 8 at% Yb:Lu2O3 ceramics were fabricated using the powders synthesized by co-precipitation method, with PAA working as dispersants. CW laser operation at 1080 nm were demonstrated.

The first CW single-crystal Fe:ZnSe laser optically pumped by Er:ZBLAN fiber laser with an output power of 2.1 W is reported. Temperature-dependent spectral characteristics and tuning (3.8-5.1 μm) are investigated.

We demonstrate that repetitive frequency shifts of a CW laser in an acousto-optic modulator generate frequency combs with > 1000 mutually coherent lines. We report self-heterodyne interferometry with 500-kHz resolution, and precise dual-comb molecular spectroscopy.

We demonstrate a new technique of arbitrary optical spectral shaping with a MHz resolution. The system, based on a single CW laser, enables the generation of radio-frequency arbitrary waveforms with bandwidth exceeding 25 GHz.

A novel method for producing optical burst pulses is demonstrated. Optical pulses having a several tens of picosecond duration, and a 100-200-ps period are generated from a gain-switched laser-diode under CW laser light injection.

We report on a Ho:YAG SCF laser inband pumped by an all-fiber Tm-laser. CW laser of 12.5 W output power and Q-switched laser with 1.44 mJ pulse energy and 7.5 ns pulse duration are demonstrated.

Using hybrid pumping of CW laser diode at 1150 nm and Tm3+-doped pulsed fiber laser at 1950 nm, we demonstrate a dual-waveband Ho3+-doped ZBLAN pulsed fiber laser at ∼2 and $\sim 3\mu \text{m}$ with low threshold of 1.7 W at 2 μm. Maximum output power of 136.6 mW and 26 mW at 2971.9 nm and 2062.3 nm were obtained with the repetition rate of 50 kHz and 25 kHz, respectively.

We present a design and analysis for the surface gain medium slab laser. This single slab laser is potential to output 12kW class laser. The experiment already achieved 5kW CW laser power output.

We developed a CW laser stabilized to a low expansion ceramic cavity with a frequency drift 7 mHz/s (δf/f ∼ 10−10 /year), which is lower than those achieved with ultra-low expansion glass cavities. OCIS codes: (140.4780) Optical resonators; (140.3425) Laser stabilization; (120.2230) Fabry-Perot

We use an intra-cavity EOM to realize high speed synchronization of dual-comb. The relative linewidth is dramatically suppressed from 300kHz to sub-hertz without ultra-stable CW laser and the ranging accuracy is greatly improved.

A 40-GHz coherent Nyquist pulse was generated from a C 2 H 2 frequency-stabilized CW fiber laser and an optical comb generator. A 1.5-THz flat-top comb was shaped into 680-fs Nyquist pulses, which are applicable to 1.28-Tbaud transmission.

We demonstrate a simple platform for reconfigurable generation of arbitrary RF chirped waveforms from a single CW laser. Our scheme is capable of generating >100 GHz bandwidth chirps with a time-bandwidth product up to ∼1300.

A CW-laser radar system developed for combustion diagnostics is described. The system is based on triangulation to attain range information. A portable system has been constructed and here we show some result from measurements in various flames, for example Rayleigh scattering thermometry and monitoring of particle distributions with high temporal and spatial resolution. The concept can equally well be based on pulsed lasers, allowing suppression of background emission through gated detection.

The spectroscopic properties of Pr:CaF2 and Pr,Gd:CaF2 crystals were measured. We report on cw laser oscillation at 642nm of Pr,Gd:CaF2 crystal. The highest laser power of 22.2mW is achieved with slope efficiency of 7.5%.

We present a short-delay fiber interferometer that employs a 90° optical hybrid to perform in-phase and quadrature detection. This instrument allows a passive and robust characterization of the frequency noise of highly stable laser oscillators.

We prepared transparent Yb:CaF 2 -LaF 3 ceramics with different combinations of doping concentrations of Yb3+ and La3+ and obtained CW laser operation with maximum output of 3.97 W. The maximum slope efficiency was as high as 73.1%.

Energy transfer parameters of Tm(5at.%),Ho(0.4at.%):KYW single crystal were investigated. A diode-pumped CW Tm,Ho:KYW microchip laser was realized. Maximum output power of 77 mW at 2070 nm was achieved in the fundamental TEM00 mode.

We present self-referencing of a CW laser via nonlinear pulse broadening of a Kerr microcomb and an electro-optic modulation (EOM) comb. Our experiments demonstrate the first phase-coherent optical-to-microwave link via f-2f self-referencing with such combs.

We have demonstrated continuous wave (CW) laser operation and the first, to the best of our knowledge, sub-200 fs mode-locked laser operation of Nd(3+)-doped Ba(Zr,Mg,Ta)O(3) ceramic. Its disordered crystalline nature exhibits a broad gain bandwidth of 30 nm with a high-emission cross section. It also has higher thermal and mechanical properties than Nd:glass. In CW operation, a maximum output power of 1.5 W under 6.2 W of absorbed pump power was obtained. In mode-locked operation, a pulse duration of 196 fs with an average power of 60 mW was successfully achieved. The laser spectrum straddled both fluorescence peaks of A-site and B-site Nd(3+) ions.

CW laser oscillation at 1020nm with a maximum output power of 2.7W was obtained from an Yb:YLF planar waveguide. Passive Q-switching (repetition rate of 2 to 10kHz and pulse duration of 40ns) was also demonstrated

The talk presents the initial evolution of the heterostructure idea in the years 1954–1963. Originally proposed for improving bipolar transistors, heterostructures made it possible to achieve cw laser at room temperature.

A Mid-IR frequency comb is upconverted to visible wavelengths by mixing with a 1064 nm cw laser in an aperiodically poled LiNBO3 waveguide. Upconversion efficiency and stability measurements are reported.

Detailed absorption and time-resolved emission data resulting from selective laser excitation are presented. True CW laser operation at red and orange laser wavelengths are reported.

Laser-diode pumped Yb3+-doped LuAG ceramic laser is reported. Maximum 2.14 W output power and 72% slope efficiency were obtained. Higher thermal conductivity and higher emission cross-section than Yb:YAG will be suitable for thin-disk laser.

A Cr4+:YAG single-crystal fiber CW laser with 180-nm tunablility using a birefringent filter was achieved, by means of a control of oscillation polarization by stress birefringence generated using fiber-holding blocks with designed grooves.

We demonstrate a stabilization of 40 Gbit/s optical DQPSK receiver using a wavelength tunable CW laser. The BER of the received data was successfully stabilized.

Efficient cw laser action of a Nd-doped mixed sesquioxide is shown at 952.7 nm. The maximum output power and slope efficiency of the quasi three-level-transition 4F3/2-4I9/2 are 356 mW and 49 % respectively.

This study presents three distinct laser methods, based on interference of a CW laser and pulsed laser ablation to create microstructures on polymeric surfaces.

We demonstrate high-power (4 W), widely-tunable (400 nm) polycrystalline Cr2+: ZnSe CW laser system utilizing an astigmatically-compensated Littrow-configuration cavity design. Using an etalon, linewidths as low as 2 nm were achieved.

Two coherent 1.5 µm frequency combs are transferred to 3.4 µm by difference-frequency generation with a 1064 nm cw laser. From a multi-heterodyne measurement, the residual linewidth between the comb teeth is resolution-limited at 200 mHz. Work of the U.S. government, not subject to copyright.

A supercontinuum-based multiwavelength laser is proposed and tested in a realistic WDM-PON scenario. BER comparison with commercial multiple channel laser array confirms this multiwavelength laser as a strong candidate for WDM-PON applications.

We introduce a new method to make gradient index (GRIN) lenses and GRIN lens arrays by exposing diffusion-driven photopolymers using a low-power CW laser. By changing the size and power of the laser beam and the exposure time, the index profile of the GRIN lens can be controlled. A novel feature of this process is that the polymer can be cast on both sides of a micro-optic, followed by exposure and diffusion to develop perfectly aligned lenses.

We report on the spectroscopic propertires and high-power diode-pumped CW laser operation of Er, Yb:YAl3(BO3)4 crystals at 1602, 1555 and 1531 nm. An output power of 1 W and a slope efficiency of 35% were demonstrated.

We present the first experiment of intracavity pumping at 914nm of an Yb:S-FAP crystal emitting at 985nm on the three-level-laser transition. We obtained 250mW output power at 985nm for 9.7W incident pump power at 808nm.

Frequency-doubing in PPKTP, PPMgSLT, and PPMgLN is studied for CW fundamental powers up to 10 W. Effects such as pump depletion and thermal dephasing are found to reduce conversion efficiency by 50% or more.

Utilising BiBO nonlinear crystal frequency doubling a Ti:Sapphire CW laser gave 100 mW at 405 nm and 53 mW at 392 nm. Stability proved excellent without servo control. Broad tunability was shown around 392 nm.

Preterm infants have a high incidence of post hemorrhagic or post infectious hydrocephalus associated with ventricular or arachnoic cysts. We have used a 2.0 micron cw-laser for laser assisted minimally invasive neuroendoscopy in complex hydrocephalus.

1.6-nm-spectrally-spaced, 8-channel semiconductor microdisk laser arrays vertically coupled to a common bus waveguide are presented. Linewidths of 0.25 nm and side mode suppression ratio (SMSR) of -20 dB are observed under continuous-wave (CW) operation.

CW laser action at room-temperature is demonstrated for the first time in Tm:Ho:LuLF. Output power in excess of 285mW, and slope efficiency of 32% were achieved experimentally.

Optical interconnects are under investigation for intrachip global communications. Low-power, high yield optical sources are required to exploit potential solutions. Two new structures are presented that enable MQWM's to be integrated with candidate fabrics, utilizing a single CW laser, waveguides, splitters, and 45-degree etched facets, providing multiple individually addressable sources.

We report on the optical properties of Yb3+-doped disordered Y3Al5O12/Y3Sc2Al4O12 (Yb: Y3ScAl4O12) ceramic lasers. Efficient cw laser oscillation of over 70% slope efficiency was obtained with over 40 nm tuning range at room temperature. We also achieved pulses as short as 580 fs with 25mW output power and 830 fs pulses with output power of 150 mW.

We report diode-pumped mode locking of Tm, Ho:YLF at 2.063 μm. Acousto-optic modulation resulted in 370 psec pulses with average output power of 100 mW when pumped with 2.6 W of cw laser diode power at room temperature. At 77 K the pulse width was similar but output power increased to 300 mW.

Room temperature, pulsed, ultraviolet upconversion laser operation from Tm3+ has been observed. At reduced temperatures, quasi cw laser operation is obtained at 347.9 nm.

CW laser action at room-temperature is demonstrated for the first time in Ho,Tm:LuLF. Output power in excess of 285mW, and slope efficiency of 32% were achieved experimentally.

Room temperature cw laser action of Yb3+-doped KY(WO4)2 and KGd(WO4)2 crystals at 1026-1044 nm has been demonstrated under pumping by 980 nm fiber-coupled InGaAs laser diode. A slope efficiency of Yb-lasers up to 53% has been obtained.

The thermal nonlinearity of air at 1.064 microns was measured to be (-5.7/spl plusmn/0.6)/spl times/10/sup -14/ cm/sup 2//W using a high-finesse Fabry-Perot cavity and a 500 mW cw laser with a 0.27 mm beam waist. The dominant contributant was identified as O/sub 2/.

We developed a reflectance imaging system with time resolution of less than one second using CW laser diodes. We measured human occipital brain during visual stimulation employing this equipment and fMRI. These results agreed well.

High-power AlGalnP laser diodes in the 670-690 nm range are needed for a variety of applications, including pumping, illumination, displays, and medicine.

We present quasi-continuous wave laser oscillation at 2975nm on the 6I7—>7Ie transition of Ho3+ in Yb3+,Ho3+:Y3Sc2Ga3O12 under laser-diode excitation at 975nm. Maximum output pulse energy was 10mJ at a repetition rate of 15Hz. Spectroscopic investigations and laser experiments with different Yb3+ concentrations and additional Eu3+ codoping are presented.

We report efficient cw laser operation of Er(l%):YLiF4 at 850 nm. The maximum output power was 765 mW with a Ti:sapphire pump laser. Intracavity frequency doubling yielded an output power of 106 mW at 425 nm.