A mode-locked dye laser pumped by a xenon ion laser

Passive mode-locking of a rhodamine 6G dye laser has been achieved, using a pulsed xenon ion laser as a pumping source. A pulse width of 5 ps and a peak power of 4 kW have been obtained. Thermal problems were encountered, which adversely affected the operation of the dye laser. Work is in progress to improve these results.     

Travelling-wave operation of a tunable cw dye laser

A ring cavity configuration for a tunable cw dye laser is described. A substantial reduction of the output bandwidth of the ring laser with increase in power for unidirectional or traveling-wave operation has been demonstrated. The advantages of the ring configuration for single-frequency operation of cw dye lasers are explored.     

Mismatch effects in synchronous pumping of the continuously operated mode-locked dye laser

A simple model is used to investigate mismatch effects on the behavior of a continuously operated dye laser synchronously pumped by a mode-locked argon-ion laser. Good mismatch control as well as appropriate gain-to-loss ratio are shown to be of major importance for laser operation in a clean picosecond pulse regime. Some characteristic features of the dye laser operation are also given.     

Two-wavelength operation of a femtosecond ring dye laser

We report on two-wavelength operation of a CPM ring dye laser employing Rhodamine 6G as gain medium and a new styryl dye as saturable absorber. Two trains of femtosecond pulses at different wavelengths are simultaneously generated under proper alignment of the laser. The secondary pulse train is attributed to the laser action of the absorber dye. Auto- and cross-correlation measurements are performed to determine the temporal characteristics of the laser in the double mode-locking regime.     

Continuous wave dye laser pumped by a HeNe laser

Continuous wave operation of a dye laser pumped at 633 nm by a HeNe laser is reported. A jet of a cooled solution of Oxazine 1 in ethanol was used as the laser medium in an asymmetric spherical cavity. With mirrors of high reflectivity a threshold as low as 10 mW could be achieved.     

A mirror-free cavity configuration for a CW ring dye laser

A new cavity configuration without mirrors is described for a CW ring dye laser. The cavity design is based on a new type of focusing prism which uses the Brewster angle of incidence and total internal reflection. Special roof prisms allow wavelength tuning. All of these elements are made from uncoated quartz thus allowing dye laser operation over a large range of wavelengths. CW operation as well as synchronously pumped mode locked operation with intracavity doubling is reported using the Rhodamine 6G dye.     

Bistable operation of a dual-wavelength synchronously mode-locked cw dye laser

Bistable operation of a dual-wavelength synchronously mode-locked cw dye laser is reported. Wavelength switching is found to depend on the pump power and the dye laser cavity lengths.     

Theoretical and experimental investigations of a passively mode-locked Nd: Glass laser

The presented theoretical model for a mode-locked Nd-glass laser simultaneously takes into account dynamics of the mode-locking dye, amplification saturation and radiation background. A systematic variation of laser parameters gives insight into the pulse formation process and allows to improve the laser design. The calculations show that it should be possible to decrease considerably the duration of light pulses of a mode-locked Nd-glass laser. Using a new mode-locking dye with a switching time of τ=2.7×10⁻¹² s we obtained stable laser operation and a pulse duration of 1.7×10⁻¹²s.     

Simple picosecond dye laser system pumped by a frequency doubled,optically compressed Q-switched mode-locked Nd:YAG laser

Using the frequency doubled output of the 3 ps pulses from a temporally compressed cw Q-switched and mode-locked Nd:YAG laser, a simple synchronously pumped dye laser was constructed to give frequency tunable operation with short pulses in the 5–10 ps range and peak powers of ～ 15 kW. A circularly scanning streak camera operating in stroboscopic mode was also used to examine pulse formation in the dye laser.     

Operation of a high power,broadly tunable infrared dye laser

We discuss the operation and performance of a ruby pumped infrared dye laser with a wide tuning range and a high out-put power. The longitudinally pumped infrared laser was operated in the Littrow configuration without an intracavity beam expander. The dye, IR 125, exhibited a tunability range that extended from 8325 Å to 9375 Å. The dye laser had a pulse duration of 20 ns and an output power of 12.5 MW with a 2.3 joule ruby pump. The maximum output power of the infrared laser was limited by the damage threshold of the tuning element.     

Efficient single mode operation of a CW ring dye laser with a Mach-Zehnder interferometer

Stable single mode operation of a ring dye laser is obtained with the combination of a Mach-Zehnder interferometer (MZI), three plate birefringent filter, a single thin etalon and a unidirectional diode. The MZI eliminates the fractional insertion loss due to beam walk-off and distortion which an intracavity etalon must introduce in order to select single frequency operation. We experimentally demonstrate the low insertion loss, single mode stability and frequency tuning of a ring dye laser using a specially designed, compact MZI. Finally, we propose MZIs with no coatings, which should permit extremely low loss broadband operation.     

Efficient distributed feedback solid state dye laser with a dynamic grating

We present the first operation of a distributed feedback solid state dye laser with a dynamic, pump-induced grating. Broadly tunable, narrow band operation in the region of 616 nm (604–649 nm) has been demonstrated with perylene red laser dye doped in poly(methyl methacrylate) (PMMA), when pumped with a frequency doubled Nd:YAG laser. Conversion efficiencies of 20%, corresponding to 35% optical-to-optical efficiency, have been measured. The laser bandwidth was between 0.01 and 0.04 nm, and smooth tuning over more than 200 GHz has been demonstrated. Received: 29 March 1999 / Published online: 24 June 1999     

Single-longitudinal-mode selection in a nanosecond-pulsed dye laser

We investigate the dynamics of the excited-state population, the cavity photon number, and the spectrum of an optically pumped nanosecond-pulsed dye laser containing bandwidth-narrowing elements in the cavity. We show that, in order to achieve single-mode operation, the pump-pulse duration has to be long enough and the dye concentration sufficiently high. This is partly due to the frequency shift of the laser spectrum during the decrease of the excited-state population towards its steady-state value. We demonstrate a single-mode dye laser, where single-mode selection is realised with the aid of an intracavity Fox–Smith interferometer. In this way we have obtained 5-ns-long pulses at the wavelength of 590 nm with a pulse energy of 6 mJ and a spectral width of 100 MHz (FWHM). Received: 3 December 2001 / Published online: 14 March 2002     

Tunable dye laser configurations

Various configurations for the successful operation of a continuous, tunable dye laser are described. Output powers as high as 100 milliwatts have been obtained using a 1.5 watt argon ion laser at 5145 Å as the optical pump for the dye laser, with a tuning range of from 5640 Å to 6150 Å.     

Demonstration of a nine lines distributed feedback dye laser using three pairs of pump beams

Controllable, maximum nine-wavelength operation of a wavefront divided, multiple beam pumped, distributed feedback dye laser (DFB), is reported for the first time. Equally spaced three to nine lines have been obtained by pumping a dye solution with three pairs of excitation beams derived from the same source. Experimental results lead to a nine line model of a distributed feedback dye laser (DFDL). The dye cell was excited by the 2nd harmonic of a laboratory built, cavity dumped, passively q switched and mode-locked Nd:YAG laser, to induce a temperature phase grating in the dye solution. Different features studied included threshold conditions, simultaneous induction of multiple gratings, impact of pump polarizations, and temporal and spectral characteristics of the emitted lines. This work on the DFDL is in agreement with most of the published results on semiconductor DFB lasers [1, 2, 3] and opens a new era of research. This multi-wavelength operation of a DFDL is based on the nonlinear effects of an overwritten multiple dynamic grating on a R6G dye solution in ethanol. PACS 42.60.By     

New efficient laser dye for pulsed and CW operation in the UV

A new laser dye for pulsed and cw operation has been synthesized which can be tuned from 362 nm up to 412 nm. For pulsed excitation with a XeCl excimer laser an energy conversion of 18.5% has been measured at the tuning maximum of the dye; this is the highest efficiency for any known dye in the UV. For cw operation a low laser threshold and a goof efficiency have been observed. The range of tuned cw dye lasers is extended by 30 nm to shorter wavelengths. The dye shows high photochemical stability even at high pump laser power.     

Infrared dye laser excited by a diode laser

A waveguide dye laser with an inner diameter of 30 μm and a length of 1.0 nm has been excited with a pulsed GaAlAs diode laser. The infrared-absorbing dye 5,5′-dichloro-11-diphenylamino-3,3′-diethyl-10,12-ethylenethiatri- carbocyanine perchlorate was used in tetramethylene sulfoxide solution. By changing dye concentration, laser wavelengths from 950 to 1005 nm were obtained.     

A grazing-incidence dye laser with an intracavity lens

The performance of a nitrogen-laser-pumped dye laser, using a grating at grazing-incidence is greatly improved by inserting a lens between the dye cell and the grating. Long term operation of the laser with a 1.1 GHz linewidth is demonstrated.     

Two-wavelength single mode grazing incidence dye laser

Two-wavelength single mode operation of a N₂-laser pumped dye laser is described. The proper choice of a grazing incidence grating and highly selective cavity elements provided a stable operation of the laser. A single mode spectrum of 310 ± 50 MHz is measured and both wavelengths are independently tunable over the entire gain profile of the R6G DN dye.     

A high-power single-mode cw dye ring laser

Due to spatial hole burning, standing-wave dye lasers require a large amount of selectivity inside the cavity for single-mode operation. The output power of these lasers is limited by losses caused by the frequency selecting elements. In a travelling-wave laser, on the other hand, spatial hole burning does not exist, thereby eliminating the need for high selectivity. A travelling-wave cw dye laser was realized by unidirectional operation of a ring laser, yielding single mode output powers of 1.2 W at 595 nm and of 55 mW in the UV-region with intracavity frequency doubling.