Spatially-hole-burned distributed feedback dye laser produced tunable single picosecond pulses

A new type of distributed feedback dye laser is described in which the Bragg grating is formed by spatial hole-burning. With a simple excimer laser pumped arrangement, single high stability 6 ps pulses were generated. The pulses were nearly transformlimited and were 33 times shorter than the rise time of the pulse which created the Bragg grating.on leave from JATE University, Department of Experimental Physics, Dóm tér 9, H-6720 Szeged, Hungary     

Two independently tunable distributed feedback dye lasers pumped by a single picosecond Nd : YAG laser

A laser system which consists of two independently tunable Distributed Feedback Dye Lasers (DFDL) pumped by 35 ps pulses at the second and third harmonics of a Nd : YAG laser is presented. The DFDLs employ a new grating-prism configuration for producing the gain grating in the laser dye solution. Thus easy switching of the pump wavelength is possible. Details of construction and characteristics of operation are reported. Examples of continuous computer controlled tuning from 400 to 750 nm are shown. The pulse durations, which are of the order of 12 ps, are discussed by comparison with experimental and theoretical data from the literature.Prof. F.P. Schäfer on the occasion of his 65th birthday.     

Generation of tunable picosecond pulses in a simple distributed feedback dye laser under N2-laser pumping

Simple possibility of single tunable picosecond pulse generation in a conventional inexpensive distributed feedback dye laser (DFDL) is demonstrated. It is shown that when a TEA N₂-laser is used for pumping no diffraction grating is necessary in the DFDL optical scheme for operation in the picosecond regime. Hence wide-range spectral tuning from 357 to 665 nm was easily achieved. When pumped with a 0.6 ns 40 kW pulse of the TEA N₂-laser the DFDL generated pulses as short as 7 ps with time-bandwidth product better than 0.6 and peak power ? 10 kW. At a repetition rate of 50 pps the shot-to-shot energy stability of a single picosecond pulse was ±18% at ±7% stability of the TEA N₂-laser.     

UV and blue picosecond pulse generation by a nitrogen-laser-pumped distributed feedback dye laser

Tunable picosecond pulse generation in the 362–420 nm spectral range is reported. The laser is simple in construction and can be easily constructed from relatively inexpensive optical and mechanical parts.     

A self-quenching picosecond distributed feedback dye laser pumped by a picosecond laser pulse

A tunable single short pulse laser system with a transform–limited bandwidth pumped by a picosecond Nd:YAG laser (ca. 120 ps pulse width) is demonstrated. With this configuration, the relaxation oscillations coming from a distributed feedback dye laser cavity are completely removed. Because the pumping pulsewidth is shorter than the lifetime of dye molecule on the upper laser state, the gain of the laser medium is depleted by the first pulse. The laser wavelength could be precisely tuned with the transform-limited bandwidth (for example, a linewidth of 0.02 nm). After amplification, we obtain a single short laser pulse energy up to 500 μJ at the pulsewidth of 8.2 ps.     

Studies on widely tunable ultra-short laser pulses using energy transfer distributed feedback dye laser

This paper presents both theoretical and experimental study of the characteristics of Nd: YAG laser pumped energy transfer distributed feedback dye laser (ETDFDL). Using theoretical model proposed, the behavior of ETDFDL such as the characteristics of donor DFDL, the acceptor DFDL, the dependence of their pulse width and output power on donor-acceptor concentrations and pump power are studied for dye mixture Rhodamine 6G and Cresyl Violet in detail. Experimentally using prism-dye cell configuration, the ETDFDL output is obtained and the output energy of DFDL is measured at the emission peaks of donor and acceptor dyes for different pump powers and donor-acceptor concentrations. In addition, the DFDL linewidth measurement has been carried out at the lasing wavelengths of the donor and acceptor dyes using Fabry-Perot etalon and the tunability of DFDL is measured to be in the wavelength range of 545-.     

A high efficiency dye laser tunable from the UV to the IR

A dye laser has been developed as a source of tunable radiation in the wavelength range 3500–3700 Å. A Variety of dyes and dye mixtures have been used to cover this range. Output powers up to 30 kW are obtained with line-widths less than 1.8 Å. A Fabry-Pérot etalon reduces the output linewidth to 0.1 Å and the peak output power by a factor of three. Second harmonic powers in excess of 2 kW have been generated from the output of this laser.     

Subpicosecond,widely tunable distributed feedback dye laser

A simple, achromatic, widely tunable distributed feedback dye laser arrangement is described. It makes use of a microscope objective, which images a transmission grating into the active medium. With this arrangement subpicosecond operation and broad tunability (400–760 nm) is reported.     

A novel pumping arrangement for tunable single picosecond pulse generation with a N2 laser pumped distributed feedback dye laser

A novel excitation scheme for a N₂ laser pumped distributed feedback dye laser is described. The dye laser generates 80–100 ps pulses with a time-bandwidth product better than 0.6. Several tuning methods are proposed, and a number are investigated experimentally. Continuous tuning over a 50 Å range without mode-hopping is demonstrated.     

Analysis of tunable picosecond pulse generation from a distributed feedback Ti：sapphire laser

A distributed feedback Ti:sapphire laser (DFTL) pumped by a 532nm Q-switched pulse is proposed for the generation of tunable picosecond pulses. With coupled rate equation model, the temporal characteristics of DFTL are obtained. The numerical solutions show that the DFTL pulse with a 50-ps pulse duration and as much as 3.SmJ pulse energy can be obtained under 40-m J, 5-ns pulse pumping. The dependence of output pulse width on the laser crystal‘s length, pumping pulse duration, and pumping rate is also discussed in detail.     

Generation of 320 fs pulses with a distributed feedback dye laser

A new achromatic distributed feedback dye laser (DFDL) arrangement is described. The experimental conditions for subpicosecond pulse generation with the new device were investigated. For the first time, stable generation of subpicosecond pulses (350 fs) at 616 nm was achieved with a DFDL. The simultaneous spectral and autocorrelation measurements showed that the amplified DFDL pulses are nearly transform limited, having a pulse form close to the sech² shape.     

Amplification of picosecond dye laser pulses

Small signal and saturated gains of picosecond pulses in Rhodamine dye amplifiers have been measured. A 17 cm amplifier produces a maximum small signal gain of ≈20, and with three amplifiers in series, peak pulse powers of > 3 GW are obtained. Mode-locking of Rhodamine 6G in the spectral range 575–600 nm is improved by employing DQOCI as saturable absorber.     

A novel picosecond distributed feedback dye laser arrangement for excimer laser pumping

A distributed feedback dye laser arrangement is described which can generate pulses at the subharmonic wavelengths of the main excimer laser lines (308 nm, 248 nm, 193 nm, etc.). The laser can be pumped with broadband lasers, such as the XeCl^* laserpumped dye laser with competing cavities. The laser is designed to be used as a part of a femtosecond, terawatt excimer laser system.     

Generation of tunable sub-picosecond pulses in the UV with a travelling wave dye laser

Received: 22 June 1998/Revised version: 3 August 1998     

An oscillator-amplifier distributed feedback dye laser system,pumped by a single TEA N2 laser

In this paper we describe a simple and inexpensive Distributed Feedback Dye Laser (DFDL) system for picosecond pulse generation. This system consists of an oscillator-amplifier DFDL, either in the grating or in the prism configuration: both stages are pumped by a single TEA nitrogen laser with improved beam quality. Single pulses having duration of 26 ps are obtained at a frequency up to 100Hz; the overall pulse-to-pulse stability is, at the maximum frequency, of about 25%. This system is particularly well-suited for time-resolved fluorescence microscopy studies where short tunable laser pulses of low energy are required.     

Generation of tunable subnanosecond laser pulses with a nitrogen laser pumped dye laser amplifier system

A simple method for generating single tunable subnanosecond dye laser pulses is described. A Rhodamin 6G dye laser is transversely pumped by a subnanosecond UV pulse of a TEA nitrogen laser. The narrowband output of the dye laser is amplified and shortened in a synchronously pumped amplifier. Narrowband pulses with a duration of 30–40 ps (fwhm) and a pulse power of 30 kW are obtained. They are tunable over the range of 580–600 nm.     

Simultaneous oscillation of several independently tunable spectral lines in a distributed feedback dye laser

A simple method is proposed which allows obtaining distributed-feedback laser action simultaneously at several spectral lines of any wavelength with independent tuning within the gain profile of the dye.     

A tunable picosecond IR laser generating multi-megawatt pulses in the range 3–8 m

We describe a versatile infrared laser system capable of generating picosecond pulses continuously tunable over the wavelength range 3.3–8.4 μm, with peak powers of 1–20 MW. The IR pulse duration is ～1.3 ps with a time-bandwidth product of ～0.3. The system uses stimulated electronic Raman scattering (SERS) in caesium vapour to shift the frequency of a picosecond dye laser into the infrared. The quantum efficiency of the Raman conversion process exceeds 40% over almost the entire tuning range. This technique can be extended to other tuning ranges in the IR by using different atomic vapours and SERS transitions.