Laser Dye Solvents Research Articles

Study of the Effect of Solvent Polarity on Transitions of Absorption and Fluorescence Spectrum of a Erythrosine Dye

In this paper, the absorption and fluorescence spectra of Erythrosine dye laser liquid solution dissolved with acetone and ethanol solution were studied in different concentrations (10-3, 10-4, 10-4 M). The results showed an increase in absorption and fluorescence intensity by increasing polarity of the solvent. Some of the linear optical properties of the prepared models were also studied. The results showed an increase in the absorbance, linear refractive index, and linear absorption coefficient with an increase in solvent polarity and the molar concentration against a decrease in the permeability value, as well as the quantitative production efficiency was calculated based on the results of the absorption spectra and fluoridation. The Purpose of the search Study the effect of solvent polarity on both absorption and fluorescence spectra, and on linear and electrical optical properties. Keywords: Erythrosine Laser dye, absorption, fluorescence spectra and Polar solvents (acetone and ethanol).

Thermo-Optical Parameters of Propylene Carbonate as a Laser Dye Solvent

The dual laser wavelength Mach-Zehnder interferometric technique is used to study the thermal and optical properties of propylene carbonate (PC), which consider as important polar dielectric solvent for many laser dyes. Using Argon and He-Ne laser at wavelengths 514.5 and 632.8 nm as a light sources and Mach-Zehnder interferometer, many thermal and optical parameters are measured and many others are calculated. The experimental technique is used for measuring the refractive index and its gradient with temperature. Applying Cauchy,s equation the dispersion of PC can be studied. Using Murphy-Alpert,s equation the gradient of refractive index dn/dT as a function of wavelength and the density versus temperature are calculated and plotted. On the other hand, the constants A and B of Cauchy,s equation as a function of temperature were studied. Additionally, using Fresnel equations many optical properties such as transmittance and reflectance as a function of incident angle, temperature and wavelength are calculated and represented. This paper gives new data measured at high frequencies to be useful and available for all workers in the field of dye lasers (designers and researchers).

Thermo-optical properties of polar dielectric laser dye solvents

This work is devoted to study the thermo-optical properties of three important pure polar dielectric laser dye solvents (aniline, pyridine and ethyl ether). Experimental measurements of the refractive index n and its thermo-optic coefficient dn/dT are carried out using dual laser Mach–Zehnder interferometric technique. The determined values of n and dn/dT are used to extract new data concerning the mentioned laser dye solvents. Applying the empirical relationship of Cauchy between the refractive index and the wavelength, the optical dispersion dn/ dλ and dn/dT, as a function of wavelength are calculated and represented. Additionally, Cauchy's constants as a function of temperature has been calculated and a comparison between the studied solvents are considered.

An Investigation of Viscosity, Relaxation Time, Tilt Angle and Radiation Force Variations by Using a Laser Interferometer Method of a Laser Dye Solvent

In the present work an interferometer laser technique was applied to determine the values and behavior of some physical parameters of one of most important laser dye solvent, benzene. Density, viscosity, relaxation time, tilt angle, radiation power, work done, and scattering factor were determine as values and behavior as function of temperature, thermal behavior d/dT, and wavelength, dispersion behavior, d/dλ. The viscosity values and its thermal behavior were determined by using the following derived equation: (dτ/dT=(3/kT2){T[ηλ(dV/dT)]−ηλVλ}. It was found that the relation between η and λ obeys the empirical relation ηT(λ)=η20(λ)+(dηdλ)Tλ. The relaxation time τ values were determined with the aid of τλ(T)=(3/kT)Vηλ(T), in addition the values of (dτ/dT)λ and (dτ/dλ)T were determined. The dispersion behavior of τ was fitted with the form τ=2.029×10−4exp(−2.060×10−4λ). The interrelation between both τ and η under the effect of temperature was verified too. The maximum radiation power exerted by one molecule of that laser dye solvent, Fmax, as a function of T and λ was investigated. It was found that its thermal behavior follows Fmax=1.366×10−31 exp(−2.31×10−2T). Its wavelength behavior was Fmax(λ)T=2.581×10−27 exp(−2.31×10−2λ). The scattering power γs was estimated with its thermal change (dγs/dT)λ and its wavelength change (dγs/dλ)T were studied. The tilt angle θ of the laser dye cell was determined with its thermal and wavelength change (dθ/dT)λ and (dθ/dλ)T, respectively. The work W and power P exerted by the dye solvent molecule were determined by using one of thermodynamical formula W=VβTP both (dW/dT)λ and (dθ/dλ)T were studied. The temperature and wavelength dependence of W was estimated during the derived relation W=3.7817×10−24(T2−T1)+4.6754×10−25(λ2−λ1). The viscosity dependence of the refractive index nT,λ(η) was studied which was found that it obeys for λ=458 nm n,λ(η)=1.4270+2.1869 × 10−47 exp(1.589×104ηT,λ−1). The density dependence of the refractive index nT,λ(π) was investigated showing a relation nT,λ(ϱ)=1.079+ϱT,λ(dn/dϱ)T,λ, from which the value of (dn/dρ)20,458=0.4954 holds. Three triplet relations were investigated: 1) the n-ρ-T relation to be nλ(T)=1.243−5.295×10−4T+0.3204ϱλ(T),2) the n-η-ϱ relation follows n(T)=−4.699×10−2−2.329×10−2ρ(T)+4.893×10−2nλ(T) and 3) the η-ρ-T relation obeying ηλ(T,ϱ)=−7.063×10−3 exp{−0.5[(T+7.101×10−2/s.005×103)+(ϱ−0.8409/0.7863)]}. All of these numerical values are selected for λ=458 nm, as an example. From these triplet relations the values of (dn/dρ)cal, (dη/dT)cal, (dη/dρ)cal, (dn/dη)cal and (dη/dn)cal were estimated and compared with that experimental values.

Study of the Optical and Physical Roles of a Dielectric Laser Dye Solvent Which Affects on the Dye Laser Operation

It is well known that when the pump laser beam incidence on the laser dye liquid it will be absorbed. This absorption tends to heat the laser active medium, which is the laser dye solution. In view of this the correlated property of that active medium well change tends to shift the operated frequency and wavelength. Therefore, one of most interested dielectric, nonpolar, laser dye solvent was selected for this investigation, which is Benzene. A laser interferometer known as Mach Zhender Interferometer (MZI) is constructed and used to measure the refractive index of the investigated solvent by counting the interfering fringes as a function of the angle of incidence of the incident laser beam. The temperature of that solvent is raised within the range 293-373 K by using a constructed heating system. The thermal behavior of the refractive index of Benzene is studied to estimate the thermo-optical coefficient of the refractive index, which is important to know the state convergence or divergence of the pump laser beam within the laser dye medium. Also, the dielectric constant of the dye solution is an important parameter for the laser operation. Therefore the dielectric constant and its thermal behavior of Benzene are calculated through the Maxwell’s relation to determine the thermal coefficient of the dielectric constant. The value of the number density which is equal the specific polarizability of the investigated solvent is estimated by using the obtained values of the refractive index and its variation with the temperature is studied too. Because the dependence of the mean polarizability of the dielectric constant through the Clausius-Mossotti relation the values of both mean polarizability and its thermal behavior are studied. In addition, since the molecular polarizability depends on the mean polarizability the value of it is determined. By using the values of mean polarizability the molecule radius is determined and using the Clausius-Mossotti relation the actual volume occupied by all molecules per unit volume are estimated. The volume expansion, through Murphy and Albert equation is calculated.

Lasing action and photodegradation of Disperse Orange 11 dye in liquid solution

We report optically pumped lasing action near 650nm of 1-amino-2-methylanthraquinone (known as Disperse Orange 11 or DO11) in the common laser dye solvents dimethylformamide and dimethylsulfoxide. Amplified spontaneous emission (ASE) was studied under second-harmonic Nd:YAG laser excitation in a transverse pumping configuration. ASE conversion efficiency is found to be comparable to other laser dyes. Photodegradation of dye solution in a micro-cuvette was investigated. While DO11 in poly(methyl methacrylate) polymer shows reversible photodegradation, in liquid solution, degradation is permanent.

Study of the refractive properties of laser dye solvents: toluene, carbon disulphide, chloroform, and benzene

This paper is devoted to the calculations of the optical and dielectric dispersion of four non and less polar laser dye solvents (toluene, carbon disulphide, chloroform and benzene). The calculations are based on measured values of refractive indices n and its temperature gradient dn/dT at two different laser wavelengths (514.5 and 632.8 nm). The thermal coefficient of refractive index dn/dT and that of permittivity de/dT as a function of the wavelength are also calculated. Additionally, other important constants as a function of temperature are graphically represented.

The necessary requirements imposed on polar dielectric laser dye solvents—II

This paper is devoted to the experimental measurements of the refractive properties for five frequently used laser dye solvents: chlorobenzene, dimethyl formamide (DMFM), dimethyl sulfoxide (DMSO), glycerin and isobutanol. The refractive indices are accurately determined using the laser Mach–Zehnder interferometric technique. The variation of the refractive index n, its thermo-optic coefficients d n/d T, and the optical dispersion d n/d λ as a function of wavelength are calculated and represented. Moreover from the data, the temperature dependence of Cauchy's constants has been determined and a comparison between the studied solvents is made.

The necessary requirements imposed on polar dielectric laser dye solvents

A laser Mach–Zehnder interferometeric technique is applied to measure the refractive index n and its thermo-optic coefficient d n/d T for five important pure polar dielectric laser dye solvents (water, methanol, ethyleneglycol, butanol and acetic acid). The measurements are carried out using the argon-ion laser wavelength 514.5 nm, and He–Ne laser of λ=632.8 nm. Applying the empirical relationship of Cauchy between the refractive index and wavelength, the following properties are calculated and represented: The refractive index, the thermo-optic constant −d n/d T, the optical dispersion −d n/d λ as a function of wavelength and Cauchy's constants against temperature. On the other hand, a discussion for comparison between the investigated solvents are given.

Molecular properties of hexane

Abstract The physical nature and properties of hexane as a laser dye solvent are discussed. Experimental facts and the dependence of the optical and electrical parameters on wavelength and temperature are provided. Additionally, high accurate calculations of more than twenty novel physical constants for hexane are given.

Molecular properties of hexane

The physical nature and properties of hexane as a laser dye solvent are discussed. Experimental facts and the dependence of the optical and electrical parameters on wavelength and temperature are provided. Additionally, high accurate calculations of more than twenty novel physical constants for hexane are given.

Mach-Zehnder Interferometer Investigations on Some Laser Dye Solvents

We have used a laser interferometric method to determine the refractive index of some laser dye solvents with a high accuracy of 5.8 x 10 -4 . The determination of refractive index (n) has been done by counting the interference fringes (N) as a function of the incidence angle of the laser beam. The absolute refractive index of pure water, dimethylsulfoxide, and different mixtures of percentages (P) 25%, 50%, 75% of dimethylsulfoxide has been measured. The relation between the bulk refractive index (nm) of these mixtures is plotted as a function of the investigated percentages. The temperature behavior of these refractive indices (dn m /dt) was studied carefully within a temperature range of (20-80°C). We have found that both the refractive index (n.) and temperature behavior of the refractive indices (dnm/dt) of different mixtures of the investigated solvents have the average index properties of the parent solvents. Also, a fitted empirical relation between nm , P, and t has been assumed as n = aPbtc with empirical constants a, b, and c. According to that equation we have recalculated of these solvent mixtures and we have found satisfying agreement with the experimental results. PACS numbers: 42.55.Mv, 78.20.Ci

Thermo-optical properties of some common laser-dye solvents

We have used a laser interferometric method to determine the refractive index of some laser dye solvents with a high accuracy 5.8 × 10 −4. The determination of refractive index ( n) was performed by counting the interfering fringes ( N) as a function of the incidence angle of the laser beam. The absolute refractive index of pure water, Dimethylsulfoxide (DMSO), and deferent mixtures, P (percentage), (25%, 50%, and 75% of DMSO) of them were measured. The relation between the bulk refractive index ( n m) of these mixtures are plotted as a function of the investigated portions ( P). The temperature behavior (d n m/d t) of these refractive indices were studied carefully within a temperature range (from 20°C to 80°C). It was found that both the refractive index ( n m) and temperature behavior of the refractive indices (d n m/d t) of that different mixtures of the investigated solvents are the average index properties of the parent solvents. Also, we did a fitted imperical relation to formulate the relation between n m, P, and t N m = ap b t c; with an imperical constants a, b, and c. According to the equation we recalculated n m of the solvent mixtures and we found an agreement with a very little difference.

Macroscopic and microscopic parameters of laser dye solvents: m-xylene and dioxane

For the laser designer and other users the optical, electrical and refractive parameters have been obtained for pure nonpolar laser dye solvents m-xylene and dioxane. The refractive index (n) and its thermo-optic constant (dn/dT) at argon laser wavelength 514.5 nm and He–Ne laser wavelength 632.8 nm, are measured. The values of n and dn/dT are used to calculate the optical permittivity ϵ=n2 and its variation with temperature dϵ/dT. Applying Cauchy's equation the optical and dielectric dispersion (dn/dλ and dϵ/dλ) are determined. The variation of −dn/dT, −dϵ/dT, molar refractivity and thermal volume expansion coefficient as a function of wavelength are calculated and represented. Furthermore Cauchy's constants A and B as a function of temperature are plotted. The specific and molar refractivities, specific and molar dispersivity total polarizability, distortion polarizability, ratio of atomic to electronic polarizability, molecular radius, relaxation time, electric susceptibility characteristic impedance, and other physical parameters were calculated. Additionally, density, thermal linear expansion coefficient and molar polarization as a function of temperature were calculated at the laser wavelengths 514.5 nm.

Measurement of the physical properties of cyclohexane using a laser interferometric technique. II

The refractive index ( n) and thermal coefficient of the refractive index (d n/d T) are measured at two laser wavelengths for the nonpolar laser dye solvent cyclohexane. The measurements are carried out using the modified laser Mach–Zehnder interferometric technique. The optical permittivity ( ϵ) and its variation with temperature are calculated. Applying the Cauchy equation, the following refractive properties are obtained: the optical dispersion d n/d λ, the dielectric dispersion d ϵ/d λ, the variation of −d n/d T, d ϵ/d T as a function of wavelength ( λ), and Cauchy's constants against temperature. Additionally, molar refractivity and thermal volume expansion coefficient versus temperature and wavelength are determined.

Invalidity of Debye theory and calculation of the molecular dipole moment for less polar laser dye solvents

The purpose of this report is to calculate the molecular permanent dipole moment of pure less polar toluene and chloroform, which are often used as laser dye solvents and many other applications. The calculations are based on the knowledge of accurate values for the refractive index and its thermal coefficient at a certain wavelength. The results indicate invalidity of Debye theory in determining the molecular permanent dipole moment, and give accurate values for the distortion polarizability. On the other hand, calculations using the Clausius–Mosotti equation lead to values for the dipole moments corrected to about 0.04165 D for toluene and 0.00574 D for chloroform. Other important physical quantities such as refractive index, density, optical permittivity, specific and molar polarization as a function of temperature are also calculated.

Thermo-optical and dielectric constants of laser dye solvents

The present work is devoted to the experimental measurements and calculations of thermo-optical and dielectric constants of four commonly used dielectric polar and nonpolar laser dye solvents; toluene, chloroform, carbon disulphide, and benzene. Using a modified high precision laser Mach–Zehnder interferometric technique the refractive index n and its thermal coefficient dn/dT were measured at two different laser wavelengths (514.5 and 632.8 nm). The measured experimental data of n and dn/dT were used in determining about 16 important physical constants and related parameters. On the other hand, the density and molar refraction as a function of temperature for the four solvents are calculated.

Laser dual-wavelength interferometric measurement of the structure and refractive parameters of carbon tetrachloride

The dual-wavelength laser Mach-Zehnder interferometric technique was used for measuring the refractive index and its gradient with temperature for the important laser dye solvent carbon tetrachloride (CTC). The Argon and HeNe laser, at wavelengths 514.5 nm and 632.8 nm respectively, are used. Applying Maxwell's and Lorentz-Lorenz equations, the structure parameters (optical permittivity, thermal coefficient of permittivity, specific and molar refraction, polarizability, molecular radius, constant dipole moment, relaxation time, impedance, … etc), of the solvent are calculated at the two wavelengths. The calculations are carried out using the measured data for the refractive index and its gradient with temperature. On the other hand the refractive index gradient with density was determined. Accordingly the optical permittivity, density and molar polarization of CTC at different temperatures were calculated. Using Caushy's equation the refractive index and permittivity as a function of wavelength were deduced. The gradient of refractive index (d n/d T) and hence the gradient of permittivity (d ϵ/d T) versus wavelength are calculated using Murphy-Alpert's equation. In addition the constants A and B of Cauchy equation are plotted as a function of temperature. Accuracy, sensitivity and discussions are treated in details.

Interferometric measurement of the physical constants of laser dye solvents

The absolute value of refractive index and its variation with temperature of benzene and chloroform at He-Ne laser wavelength 6328 Å are measured. The measurements are carried out using laser interferometric technique. This technique is based on the shift of interference pattern when rotating the sample in one arm of a newly developed Mach–Zehnder interferometer. The refractive index shows a linear relationship with temperature in the range of interest. The thermal refractive index coefficients of benzene and chloroform are all negative. Applying Maxwell’s theory and Lorentz–Lorenz function, the obtained results are used for calculating the optical permittivity (or dielectric susceptibility) as a function of temperature and many other important related physical constants.

Laser dye stability. Part 2

The lifetime of a laser dye solvent system is experimentally shown to increase with increased energy per excitation flash. By measuring the variation in laser output with differing input energies, it is shown that degradation constants can be determined. These degradation constants can be used to give the laser output as a quadratic function, a degradation equation, involving the input energy per flash and the total input energy per unit volume as independent variables. This degradation equation, in turn, can be reduced to a relationship between the half-life and the input energy per flash. The half-life for a given input energy per flash is found to approach an upper limit which can be derived using the degradation constants. The effects upon a laser dye system lifetime of varying the concentration of the dye and mirror reflectivity are discussed. Experimental evidence is presented showing that these two parameters do not affect the upper limit half-life for coumarin 1 in ethanol.