Operation Of Dye Laser Research Articles

Single-mode-fiber ring dye laser

Pulsed dye-laser operation in a single-mode fiber is demonstrated by incorporating an evanescent field amplifier into an all-fiber ring resonator. Laser threshold is obtained with 60 mW of pump power. Characteristics of the vanescent fiber amplifier are investigated as functions of pump power and dye solution index.

Laser spectroscopy of CuS: Analysis of the A2Σ-X2Πi system

Laser excitation spectra of the A2Σ-X2Πi system have been recorded for 63CuS and 65CuS isotopic molecules with a single-mode dye laser operating in the region 17000–18000 cm−1. For highly overlapped sequences, use of a monochromator as a narrow band filter was necessary to allow rotational analysis. A simultaneous fit of all eight analyzed bands has led to the following spectroscopic constants for 63CuS (in cm−1): StatevTvBvDv × 106γvpvav × 106A2Σ−017924.335 (7)0.17989 (4)0.177 (7)0.03853 (7)X2Π121842.574 (7)0.18701 (4)0.163 (7)0.01496 (9)0432.566 (6)0.18818 (4)0.162 (7)0.01508 (9)X2Π321411.289 (7)0.18724 (4)0.184 (7)−0.96 (6)0—0.18839 (4)0.160 (7)−0.11 (6) (Numbers in parentheses are 3σ uncertainties.) Indirect configuration assignments combined with spectroscopic analysis lead to a Σ− symmetry for the upper state.

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.

Characterizing laser dye performance

Several measures of laser performance are investigated for a generic dye laser operating under conditions where the input energy is limited by a maximum value and the output is required to be above some minimum value. Dimensionless expressions are developed that show the interrelationships between the efficiency, the number of laser pulses for a unit volume of dye solution, and the total laser output per volume of dye solution. For one of the performance measures, the total laser output per unit volume of dye solution, the initial slope efficiency divided by a parameter characteristic of the degradation process,k0/c, is identified as a reasonable figure of merit. It is readily evaluated from experimental degradation data and has reasonably simple properties relative to transfer between laser systems.

Tunable passive colliding-pulse mode locking in a linear dye laser

We demonstrate the versatile operation of a linear femtosecond dye laser that terminates in an antiresonant ring for passive colliding-pulse mode locking. The system combines several advantages of a conventional ring laser with those of a linear laser and in addition offers the unique possibility of continuously tuning the pulse-repetition rate over a 1-GHz band. Moreover, the geometry allows a commercial linear laser to be mode locked easily without significant cavity changes.

Ar-ion-laser-pumped infrared dye laser at 875–1084 nm

High-efficiency high-power cw dye-laser operation has been achieved from 875 to 1084 nm by pumping two styryl derivatives with an Ar-ion laser. Peak output powers as high as 900 and 750 mW were obtained around 925 and 980 nm, respectively.

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.

Improvement of efficiency of N2 laser‐pumped infrared dye lasers through energy transfer excitation

AbstractThe N2 laser‐pumped dye laser is an important coherent light source used very widely in research applications of optical properties of various objects. However, it is difficult to obtain highly efficient laser operation in the near infrared range. This paper considers the operation and development of an energy transfer dye laser (ETDL) and the cascade ETDL operation in the near infrared range with the aim of improving the efficiency of the N2 laser‐pumped infrared dye laser. As a result, Nile‐Blue‐HITC ETDL and Nile‐Blue‐ Cryptocyanine ETDL operating in the range of 700 nm ‐ 900 nm have been realized. Furthermore, in the ternary dye mixture system with addition of Rhodamine‐B to these dye mixtures, the cascade ETDL operations also occur efficiently. the high efficiency of the N2 laser‐pumped near infrared dye lasers has been realized by means of these ETDLs, and a wide tuning range laser operation has been obtained.

A wideband frequency-offset-locked dye laser spectrometer using a schottky barrier mixer

Precise frequency-controlled operation of a single-mode ring dye laser with respect to another is reported at a frequency difference of 234 GHz. This extension of the technique of laser frequency offset locking into the microwave range has been achieved by mixing the two laser lines with the harmonics of a suitable microwave frequency on a Schottky barrier mixer. The capability of this spectrometer was demonstrated by a frequency measurement of the transition 1s 5–2p 8 in 20Ne with an uncertainty of 1 × 10 -9.

Argon pumped dye laser operation in the 690-700 nm region

A study of an argon pumped new red laser dye and mixture is reported for operation in the 690-700 nm region. Best reliability was achieved with the dye LD688.

Continuously tunable energy transfer laser operation in four‐dye mixture systems

AbstractTheoretical as well as experimental investigation of the energy transfer dye laser (ETDL) operation has been performed, aimed at development of a dye laser which covers a wide wavelength range without exchanging a dye mixture. the following two dye mixtures are shown to be very effective: Rhodamine 6(R6G)‐Safrain.T(ST)‐Cresyl Violet (CV)‐Nile Blue(NB) and Coumarin 1(C1)‐ Acriflavine(A)‐Uranine(U)‐R6G. Their desirable dye concentrations are derived and the tuning characteristics are measured. Conclusively, a continuous tuning was achieved over 130 nm in either case, and hence almost the entire visible range is covered with these two ETDL's.

Nozzle design yielding interferometrically flat fluid jets for use in single-mode dye lasers

Fundamentals and design principles are presented for the generation of interferometrically flat jets of viscous fluids. The jet quality is optically analyzed and nozzle performance investigated in cw single-mode dye laser operation. A nozzle providing a dye jet with an optically flat area of 9 mm2 is described. It produces a single-mode bandwidth of ∼5 MHz without any active stabilization.

Survey of lasers for spectroscopic use: optical and ultraviolet

The principles and operation of narrow-bandwidth and mode-locked tunable dye lasers are described and the extension of their effective tuning ranges by harmonic generation and stimulated Raman scattering is discussed. Methods of producing highpower ultraviolet radiation using excimer lasers and techniques for vacuum u.v. generation by frequency mixing are also described.

CW dye laser operation at 200 W pump power

A continuously operating jet stream dye laser was pumped by a multiwavelength-multimode argon-ion-laser with a pump power up to 200 W. Rhodamine 6G-chloride was dissolved in a water-polyvinylalcohol-ammonyx solution. The dye laser was prism-tunable between 560 and 650 nm with maximum output power at 600 nm. The maximum output power of the cw dye laser was 43 W without tuning element and 33 W with a prism placed inside the cavity. Operation of a jet stream dye laser with a pump power higher than 200 W and an efficiency of about 30% seems to be possible.

Narrow linewidth operation of a flashlamp-pumped dye laser

The authors describe a flashlamp-pumped dye laser system that produces more photons per laser pulse than in nitrogen or Nd:YAG laser-pumped dye lasers. The system uses both a grazing incidence grating and a Littrow mounted grating in conjunction with an elliptical cavity. An observed linewidth of less than 600 MHz is reported for single laser pulses. (AIP)

Efficient energy transfer dye lasers in spectral region of near ultraviolet to violet

AbstractAn experiment was performed on the operation and development of energy transfer dye lasers (ETDL), using scintillator dye mixture to obtain higher efficiency and an expanded range of wavelengths in the ultraviolet to violet region, in which an N2 laser is used for excitation. High lasing efficiencies were observed with αNPO‐dimethyl. POPOP, PPF‐αNPO, and some other dye mixtures, and overlapping lasing was observed, involving the donor and acceptor dye laser regions. A blue shift of the oscillation frequency was analyzed theoretically, and the theoretical results concerning the dependence of the oscillation wavelength on laser power and donor dye concentration were in good agreement with observations.

Energy transfer dye mixture for argon-pumped dye laser operation in the 700 to 800 nm region

The tunable wavelength region for argon-pumped dye lasers is extended to 805 nm using a binary energy transfer dye mixture. Efficiency as high as 13% was observed at the peak wavelength of 730 nm.

The optical–optical double resonance spectrum of 7Li2 excited by a single tunable cw laser

The two-photon excitation spectrum of 7Li2 produced by a single tunable cw dye laser operating between 570 and 650 nm has been observed using ultraviolet fluorescence detection. The spectrum arises from optical–optical double resonance transitions from the X 1Σg+ ground electronic state to the F 1Σg+ and G 1Πg excited states via the A 1Σu+ intermediate state, in which vibrational and rotational relaxation also take place. Using the known molecular constants for these states, a theoretically predicted spectrum was found from which the prominent lines in the experimental spectrum could be assigned. The multiphoton ionization spectrum of Li2, previously observed and interpreted in terms of bound–free–bound triplet absorption bands, can be explained as OODR transitions among the above states followed by photoionization.

High power single-mode cw dye laser with Michelson mode selector

The application of a Michelson mode selector for high power single-mode operation of a cw dye laser is reported. By employing the selector for compensation of spatial hole burning effects in a standing-wave cavity, a tunable single-mode output power of 1 W has been obtained at 590 nm. A double Michelson selector has also been applied with the spatial hole burning taken into account.

Kinetics of CH radical reactions with selected molecules at room temperature

The rate constants for reactions of the CH radical with selected molecules relevant to hydrocarbon combustion systems have been measured at room temperature. The CH radical was generated by multiphoton dissociation of CHBr 3 at 193 nm and monitored by laser induced fluorescence using a pulsed tunable dye laser operating in the 420–440 nm region. The mechanisms of these reactions have been discussed in terms of observed rates and other thermochemical data.