Showing papers on "Buffer gas published in 2010"
TL;DR: The effect of moisture and organic contaminants in the buffer gas on the mobility of IMS standards and analytes was investigated for the first time using IMS directly coupled to mass spectrometry.
Abstract: In ion mobility spectrometry (IMS), reduced mobility values (K0) are used as a qualitative measure of gas phase ions, and are reported in the literature as absolute values. Unfortunately, these values do not always match with those collected in the field. One reason for this discrepancy is that the buffer gas may be contaminated with moisture or other volatile compounds. In this study, the effect of moisture and organic contaminants in the buffer gas on the mobility of IMS standards and analytes was investigated for the first time using IMS directly coupled to mass spectrometry. 2,4-Dimethylpyridine, 2,6-di-tert-butylpyridine (DTBP), and tetrabutylammonium, tetrapropylammonium, tetraethylammonium, and tetramethylammonium chlorides were used as chemical standards. In general, the mobility of IMS standard product ions was not affected by small amounts of contamination while the mobilities of many analytes were affected. In the presence of contaminants in the buffer gas, the mobility of analyte ions is often decreased by forming ion–molecule clusters with the contaminant. To ensure the measurement of accurate reduced mobility values, two IMS standards are required: an instrument and a mobility standard. An instrument standard is not affected by contaminants in the buffer gas, and provides an accurate measurement of the instrumental parameters, such as voltage, drift length, pressure, and temperature. The mobility standard behaves like an analyte ion in that the compound's mobility is affected by low levels of contamination in the buffer gas. Prudent use of both of these standards can lead to improved measurement of accurate reduced mobility values.
96 citations
TL;DR: In this article, the effect of TWIMS wave height parameters on the calibration is addressed by comparison of theoretical collision cross-sections calculated using helium and nitrogen radii with TWIMs-MS cross-section measurements determined in either helium or nitrogen buffer gases.
94 citations
TL;DR: It is shown that optical pumping of a trace contamination of Rb present in K metal results in a 4.5 times higher polarization of K than direct Optical pumping of K in the absence of N2.
Abstract: Optical pumping of an optically thick atomic vapor typically requires a quenching buffer gas, such as N2, to prevent radiation trapping of unpolarized photons which would depolarize the atoms. We show that optical pumping of a trace contamination of Rb present in K metal results in a 4.5 times higher polarization of K than direct optical pumping of K in the absence of N2. Such spin-exchange polarization transfer from optically thin species is useful in a variety of areas, including spin-polarized nuclear scattering targets and electron beams, quantum-nondemolition spin measurements, and ultrasensitive magnetometry.
84 citations
TL;DR: Analysis is presented that indicates that this combination of techniques will be applicable to many comparably sized molecules, and this technique can also be combined with cryogenic beam methods to produce cold, high flux, continuous molecular beams.
Abstract: Cold and dense samples of naphthalene (C10H8) are produced using buffer gas cooling in combination with rapid, high flow molecule injection. The observed naphthalene density is n ≈ 1011 cm−3 over a volume of a few cm3 at a temperature of 6 K. We observe naphthalene–naphthalene collisions through two-body loss of naphthalene with a loss cross section of σ– = 1.4 × 10−14 cm2. Analysis is presented that indicates that this combination of techniques will be applicable to many comparably sized molecules. This technique can also be combined with cryogenic beam methods1 to produce cold, high flux, continuous molecular beams.
60 citations
01 Jan 2010
TL;DR: The first realization of Bose-Einstein condensation using buffer-gas cooling using a broadly general method which relies neither on laser cooling nor unique atom-surface properties was reported in this paper.
Abstract: We report the creation of a Bose-Einstein condensate using buffer-gas cooling, the first realization of Bose-Einstein condensation using a broadly general method which relies neither on laser cooling nor unique atom-surface properties. Metastable helium ((4)He*) is buffer-gas cooled, magnetically trapped, and evaporatively cooled to quantum degeneracy. 10(11) atoms are initially trapped, leading to Bose-Einstein condensation at a critical temperature of 5 microK and threshold atom number of 1.1 x 10(6). This method is applicable to a wide array of paramagnetic atoms and molecules, many of which are impractical to laser cool and impossible to surface cool.
58 citations
TL;DR: The gas-phase laser-induced fluorescence of an ensemble of buffer gas-cooled Rhodamine 6G cations stored in a quadrupole ion trap at 90 K was studied, and a lower bound for the half-life was found to be approximately 2 s.
Abstract: We have studied the gas-phase laser-induced fluorescence of an ensemble of buffer gas-cooled Rhodamine 6G cations (R6G(+)) stored in a quadrupole ion trap at 90 K. The fluorescence resulting from excitation with continuous-wave 488 nm radiation was observed to disappear almost completely on a time scale of seconds, dependent in detail on the excitation laser fluence. Such decay can be explained by the accumulation of R6G(+) in a dark triplet state. This in turn facilitates the first lifetime determination of the lowest triplet state of free R6G(+) by direct ground-state recovery measurements. A lower bound for the half-life was found to be approximately 2 s. Adding oxygen in a volume fraction of 1% to the buffer gas leads to efficient quenching of the triplet state and correspondingly to complete suppression of the fluorescence intensity decay. Different rare gases were applied as buffers for collisional cooling, but no significant changes in the fluorescence properties were found.
48 citations
TL;DR: In this article, a single ion is confined by a radiofrequency trap in an ultracold atomic gas and the steady state energy distribution of the ion is determined by its kinetics in the radiofrequency field rather than the temperature of the buffer gas.
Abstract: The immersion of a single ion confined by a radiofrequency trap in an ultracold atomic gas extends the concept of buffer gas cooling to a new temperature regime. The steady state energy distribution of the ion is determined by its kinetics in the radiofrequency field rather than the temperature of the buffer gas. Moreover, the finite size of the ultracold gas facilitates the observation of back-action of the ion onto the buffer gas. We numerically investigate the system's properties depending on atom-ion mass ratio, trap geometry, differential cross-section, and non-uniform neutral atom density distribution. Experimental results are well reproduced by our model considering only elastic collisions. We identify excess micromotion to set the typical scale for the ion energy statistics and explore the applicability of the mobility collision cross-section to the ultracold regime.
48 citations
TL;DR: The relative insensitivity of tetraalkylammonium ions and DTBP to the introduction of 2-butanol into the buffer gas was explained by steric hindrance of the four alkyl substituents in tetraalklammonia ions and the two tert-butyl groups in DTBP, which shielded the positive charge of the ion from the attachment of 2 -butanol molecules.
44 citations
TL;DR: In this paper, a 3.9 T magnetic trap was used to trap NH molecules with 1/e lifetimes exceeding 20 s. Long molecule trapping times were attained through rapid pumpout of residual buffer gas.
Abstract: Buffer gas cooling is used to trap NH molecules with 1/e lifetimes exceeding 20 s. Helium vapor generated by laser desorption of a helium film is employed to thermalize 10 5 molecules at a temperature of 500 mK in a 3.9 T magnetic trap. Long molecule trapping times are attained through rapid pumpout of residual buffer gas. Molecules experience a helium background gas density below 1 × 10 12 cm −3 . Contents
35 citations
TL;DR: In this article, the inversion temperature of a single Neon buffer gas vapour microcell was measured to be about 80°C for two different samples and a proposal to develop chip scale atomic clocks with improved long-term frequency stability, simpler configuration (a single buffer gas instead of a buffer gas mixture) and relaxed constraints on pressure accuracy during the cell filling procedure was presented.
Abstract: Presented is the observation of a quadratic temperature dependence of the Cs 0-0 ground state hyperfine resonance frequency in a single Neon (Ne) buffer gas vapour microcell. The inversion temperature, expected to be theoretically independent of the buffer gas pressure, is measured to be about 80°C for two different samples. A proposal to develop chip scale atomic clocks with improved long-term frequency stability, simpler configuration (a single buffer gas instead of a buffer gas mixture) and then relaxed constraints on pressure accuracy during the cell filling procedure is presented.
35 citations
TL;DR: In this paper, a stable and convenient optical system to realize the forward phase-matching geometry for degenerate four-wave mixing (DFWM) is demonstrated in the mid-infrared spectral region by measuring DFWM signals generated in acetylene (C2H2) and hydrogen chloride (HCl) molecules by probing the fundamental ro-vibrational transitions.
Abstract: A stable and convenient optical system to realize the forward phase-matching geometry for degenerate four-wave mixing (DFWM) is demonstrated in the mid-infrared spectral region by measuring DFWM signals generated in acetylene (C2H2) and hydrogen chloride (HCl) molecules by probing the fundamental ro-vibrational transitions. IR laser pulses tunable from 2900 cm−1 to 3350 cm−1 with a 0.025 cm−1 linewidth were obtained using a laser system composed of an injection seeded Nd:YAG laser, a dye laser, and a frequency mixing unit. At room temperature and atmospheric pressure, a detection limit of 35 ppm (∼ 9.5×1014 molecules/cm3) for C2H2 was achieved in a gas flow of a C2H2/N2 mixture by scanning the P(11) line of the (010(11)0)–(0000000) band. The detection limit of the HCl molecule was measured to be 25 ppm (∼6.8×1014 molecules/cm3) in the same environment by probing the R(4) line. The dependences of signal intensities on molecular concentrations and laser pulse energies were demonstrated using C2H2 as the target species. The variations of the signal line shapes with changes in the buffer gas pressures and laser intensities were recorded and analyzed. The experimental setup demonstrated in this work facilitates the practical implementation of in situ, sensitive molecular species sensing with species-specific, spatial and temporal resolution in the spectral region of 2.7–3.3 μm (3000–3700 in cm−1), where various molecular species important in combustion have absorption bands.
TL;DR: In this article, electron-beam generation by open discharges was examined at gas pressures up to 20 Torr and covered all inert gases, and it was concluded that the production of electrons from cold cathode was of photoemissive nature, enabling the generation of high-intensity electron beams in any noble gas or in a mixture of a noble gas with molecular gases irrespective of cathode material.
Abstract: In the present study, electron-beam generation by open discharges was examined. The study was performed at gas pressures up to 20 Torr, and covered all inert gases. At voltages up to 8 kV, electron-beam currents up to 1600 A with current density ∼130 A/cm2 and a beam generation efficiency in excess of 93% were obtained. The production of electrons from cold cathode was concluded to be of photoemissive nature, enabling the production of high-intensity electron beams in any noble gas or in a mixture of a noble gas with molecular gases irrespective of cathode material.
TL;DR: In this paper, the authors presented the transformation in the Hanle configuration of the transmission that results from coherent population trapping (CPT) into the level-crossing absorption (LCA) that resulted from the single-photon optical pumping in the Rb vapor cell with a Ne buffer gas when the polarization of the laser field is changed from linear to circular.
Abstract: We present the transformation in the Hanle configuration of the transmission that results from coherent population trapping (CPT) into the level-crossing absorption (LCA) that results from the single-photon optical pumping in the $^{87}\mathrm{Rb}$ ${D}_{1}$ line of a Rb vapor cell with a Ne buffer gas when the polarization of the laser field is changed from linear to circular. The LCA spectrum, with a narrow spectral width of $2.4$ mG ($1.7$ kHz), was observed in the ${F}_{g}\ensuremath{\rightarrow}{F}_{e}\ensuremath{\leqslant}{F}_{g}$ transition with the circularly polarized laser. This may be because the LCA is both related to the transverse magnetic field and the atom-laser interaction time resulting from diffusive atomic motion in the cell with the buffer gas. The CPT and LCA spectra were calculated numerically using the full density matrix equations for the relevant magnetic sublevels of the hyperfine levels, considering the residual magnetic fields perpendicular to laser propagation and the collision effects resulting from the buffer gas. There was good qualitative agreement between theoretical and experimental results.
TL;DR: The theoretical and measured binary and ternary recombination rate coefficients obtained for and ions are in good agreement.
Abstract: Measurements of recombination rate coefficients of binary and ternary recombination of and ions with electrons in a low temperature plasma are described. The experiments were carried out in the afterglow plasma in helium with a small admixture of Ar and parent gas (H2 or D2). For both ions a linear increase of measured apparent binary recombination rate coefficients (αeff) with increasing helium density was observed: αeff = αBIN + K He[He]. From the measured dependencies, we have obtained for both ions the binary (αBIN) and the ternary (K He) rate coefficients and their temperature dependence. For the description of observed ternary recombination a mechanism with two subsequent rate determining steps is proposed. In the first step, in + e− (or + e−) collision, a rotationally excited long-lived Rydberg molecule (or ) is formed. In the following step (or ) collides with a He atom of the buffer gas and this collision prevents autoionization of (or ). Lifetimes of the formed (or ) and corresponding ternary re...
TL;DR: In this paper, a theoretical study on the transmission spectra of an arbitrarily polarized laser beam through a rubidium cell with or without a buffer gas in Hanle-type coherent population trapping (CPT) was performed.
Abstract: This paper reports a theoretical study on the transmission spectra of an arbitrarily polarized laser beam through a rubidium cell with or without a buffer gas in Hanle-type coherent population trapping (CPT). This study examined how laser polarization, transverse magnetic field, and collisions with buffer gas affects the spectrum. The transmission spectrum due to CPT and the absorption spectrum due to the level crossing absorption (LCA) were calculated according to the laser polarization. The results show that the LCA is strongly dependent on the transverse magnetic field and interaction time of the atoms with a laser light via collisions with the buffer gas. In addition, the spectral shape of the calculated Hanle spectrum is closely related to the direction between the (stray) transverse magnetic field and polarization of the laser.
TL;DR: In this paper, the authors present an experimental setup that allows the injection of charged nanoparticles in a diameter range of 3-15 nm into a vacuum chamber and their storage there in an electrodynamic cage.
Abstract: We present an experimental setup that allows the injection of charged nanoparticles in a diameter range of 3–15 nm into a vacuum chamber and their storage there in an electrodynamic cage. The nanoparticle density in the trap is limited by space charge and can be several orders of magnitude higher than in a free nanoparticle beam. The setup provides for the first time a tool for the application of advanced techniques of spectroscopy to free nanoparticles in this size range. It consists of a combination of (1) a plasma discharge nanoparticle source that generates a high density of nanoparticles of various composition suspended in helium carrier gas at a pressure of about 10–150 mbar, (2) an aerodynamic lens optimized for small particles (diameter 3–15 nm) that forms a well-collimated beam of charged nanoparticles and focuses it into (3) an octopole ion trap operated at low frequencies and filled with helium buffer gas at 10−2 mbar in order to moderate and store the nanoparticles at densities of more than 10...
Patent•
17 Jun 2010TL;DR: In this article, a gas filling apparatus (2) in the gas filling system (1) includes a precooler (18) for cooling hydrogen gas supplied from the gas supply source (11) and discharges the hydrogen gas cooled by the precoolers to fill the gas tank (30).
Abstract: A gas filling apparatus (2) in the gas filling system (1) includes a precooler (18) for cooling hydrogen gas supplied from the gas supply source (11) and discharges the hydrogen gas cooled by the precooler (18) to fill the hydrogen gas into the gas tank (30). The temperature of the hydrogen gas cooled by the precooler (18) is detected by a gas temperature sensor (T) that detects, upstream of the gas tank (30), a temperature of the hydrogen gas cooled by the precooler (18). A flow rate controller (16) controls a filling flow rate of the hydrogen gas to be filled into the gas tank (30), based on the detected. temperature of the hydrogen gas. For example, when the detected temperature of the hydrogen gas is high, the filling flow rate' is reduced as compared to that when the detected temperature of the hydrogen gas is lower.
TL;DR: In this article, the processes in the magnetron discharge involving metal atoms and metal clusters are analyzed and the efficiency of conversion of metal atoms in clusters is found in stationary magnetron discharging.
Abstract: The processes in the magnetron discharge involving metal atoms and metal clusters are analyzed. The efficiency of conversion of metal atoms in clusters is found in stationary magnetron discharge. The scheme of pulse magnetron discharge is considered with a variation of the buffer gas pressure after the electric pulse that provides an increase in the cluster generation efficiency in comparison with the stationary discharge.
15 Mar 2010-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: In this paper, the authors studied the effects of the passage of a primary beam through an ion guide via the dynamic time profiles of yttrium and related molecular compounds, and showed that the accessibility of a neutral fraction for laser ionization is restricted to the nozzle region in the presence of a weak plasma.
Abstract: The laser ion source at the IGISOL facility, Jyvaskyla, has been used to study the effects of the passage of a primary beam through an ion guide via the dynamic time profiles of yttrium and related molecular compounds. The accessibility of a neutral fraction for laser ionization is shown to be restricted to the nozzle region in the presence of a weak plasma. The survival of this neutral fraction cannot be explained by recombination of the buffer gas alone and perhaps indicates a suppression of the transport of ions due to a plasma-generated electric field. The concept of a competition between the processes that create and destroy the ion of interest is used to explain the different trends in the ratio of yttrium to yttrium oxide following the extraction of a stopped primary beam of 89Y21+ in both helium and argon buffer gases.
TL;DR: In the past decade, the helium gas field ion source (GFIS) performance was vastly advanced, permitting the development of the helium ion microscope (HIM) and neon GFIS as discussed by the authors.
Abstract: Soon after its development in 1955, the gas field ion source (GFIS) was pursued as the source of positive ions for focused ion beam (FIB) instruments [1]. Within the semiconductor industry, such FIB instruments are of critical importance for their failure analysis (FA), circuit edit (CE), and TEM sample preparation. However the GFIS development efforts were hampered by issues related to the source lifetime, and the short and long term temporal stability. The commercial gallium liquid metal ion source (Ga-LMIS) has served as the ion source of choice for the past 30 years with some recognized shortcomings arising from the probe size, electrical contamination, optical opacity, etc [2]. These shortcomings have produced a growing interest in FIBs with other ion species. In the past decade, the helium GFIS performance was vastly advanced – permitting the development of the helium ion microscope (HIM). In the past year, these same advances were applied to a neon GFIS.
TL;DR: In this article, the line shape parameters of rovibrational transitions of water vapour belonging to the (2ν1 + ν2+ ν3) overtone band due to collisions between absorber molecules and noble gas helium have been measured in the spectral range between 11988.494 cm−1 and 12218.829 cm −1 using NIR diode laser spectrometer.
Abstract: The line shape parameters of rovibrational transitions of water vapour belonging to the (2ν1 + ν2 + ν3) overtone band due to collisions between absorber molecules and noble gas helium have been measured in the spectral range between 11988.494 cm−1 and 12218.829 cm−1 using NIR diode laser spectrometer. In addition nitrogen and air broadening effects on some water vapour transitions belonging to the same band have also been studied. Wavelength modulation spectroscopy along with phase sensitive detection technique are used to record first derivative (1f) signal of buffer gas broadened water vapour transitions. Observed line shapes are fitted to standard Voigt profiles by non-linear least squares fitting program to extract the line shape parameters, like line strength and pressure broadening coefficients. The broadening effects induced by different types of buffer gases on water vapour line shapes are compared. Rotational quantum number (J) dependence of broadening coefficients of water vapour transitions is ...
01 Jan 2010
TL;DR: In this paper, a suite of tools for cooling a wide variety of molecules, and for creating bright, cold, and slow molecular beams is presented, based on buffer gas techniques.
Abstract: The vast majority of techniques for cooling, manipulating, and trapping molecules demonstrated to date rely on specific and unusual features of the molecular species being studied. We present here a suite of tools for cooling a wide variety of molecules, and for creating bright, cold, and slow molecular beams. The buffer gas techniques used depend only on very general qualities of the molecule and we demonstrate them to be widely applicable. Current and future applications to studies of new physics and chemistry are presented.
TL;DR: In this article, the authors measured microwave double resonances in a wall-coated Rb vapor cell as a function of additional buffer-gas pressure and found that at intermediate pressures the lineshapes of the microwave resonances become asymmetric with a low-frequency tail.
Abstract: Microwave double resonances were measured in a wall-coated Rb vapor cell as a function of additional buffer-gas pressure. These data were compared with similar measurements in an uncoated cell. It was found that the linewidth in the coated spherical cell of diameter 1.6 cm displays a distinct maximum around 0.2 kPa. This agrees well with theoretical solutions of the diffusion equation, assuming a complex reflection coefficient at the wall. It was also found that at intermediate pressures the lineshapes of the microwave resonances become asymmetric with a low-frequency tail. This agrees with the explanation that where the alkali mean free path is substantially smaller than the average distance between wall collisions at zero pressure, there exist two classes of atoms in the cell. The atoms that get trapped near the walls accumulate much larger phase shifts than those toward the center of the cell. This effect is not seen in the longitudinal relaxation rate, indicating that it is related to a phase-shift effect.
Patent•
22 Apr 2010TL;DR: In this paper, a system, in certain embodiments, includes a seal assembly having a seal body including an inlet buffer port and an outlet eduction port, which is configured to receive a compressed buffer gas, such as shop air, injected into the buffer port.
Abstract: A system, in certain embodiments, includes a seal assembly having a seal body The seal body includes an inlet buffer port and an outlet eduction port The inlet buffer port is configured to receive a compressed buffer gas, such as shop air, which is injected into the inlet buffer port The compressed buffer gas blocks the flow of a compressed process gas, such as land fill gas, by opposing the flow of the compressed process gas through the seal assembly Both the compressed buffer gas and the compressed process gas may be expelled through the outlet eduction port
TL;DR: In this article, the optimal buffer-gas condition for achieving low noise in room temperature optical-pumped magnetometers (OPMs) was determined, where various buffer gases (helium, neon, argon, and nitrogen) were tested.
Abstract: The optimal buffer-gas condition for achieving low noise in room temperature optical-pumped magnetometers (OPMs) was determined. To find this optimal condition, various buffer gases (helium, neon, argon, and nitrogen) filled in cesium cells at pressures of 1, 10, 50, 300, or 1000 Torr were tested. Magnetic-resonance signal was detected by sweeping rf frequency, and maximum intensity (Imax) and line width (Δf) in the magnetic-resonance spectra were measured. As an appropriate figure of merit for OPMs, the "α value" (i.e., Imax/Δf) is defined. It was found that the α value of the cells decreased as gas pressure increased. The α value obtained from the cell filled with neon gas (at 1 Torr) at optimal rf field of 50 nT was the largest. It was inferred from these results that the spin-destruction collision between cesium atoms and the buffer gas has a significant influence on the α value.
Patent•
26 Feb 2010
TL;DR: In this paper, the authors propose a fluorine gas supply system for semiconductor processing devices in a large quantity and in a precise concentration, where a mixed gas stored in a buffer tank is introduced into a gas introducing pipeline before the mixed gas is adjusted in the buffer tank.
Abstract: [Task] It is a task to provide a fluorine gas supply system which can stably supply fluorine gas generated by a fluorine gas generation device to a semiconductor processing device in a large quantity and in a precise concentration. [Means for solving task] In the fluorine gas supply system, a mixed gas stored in a buffer tank is introduced into a gas introducing piping before the mixed gas is adjusted in the buffer tank to circulate the mixed gas and a monitoring device is disposed which measures a fluorine gas concentration within the mixed gas so that, in response to the obtained fluorine gas concentration, a flow quantity of inert gas supply source can be adjusted.
27 Jul 2010-Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering
TL;DR: It was found that a cylindrical cell with many acoustic filters considerably dampens the noise level and also argon as a buffer gas improves the photoacoustic signal level and this combination substantially improved the signal to noise ratio and the limit of detection.
Abstract: Photoacoustic (PA) gas sensor for the detection of hazardous NO2 with detection limit as low as few part per billion by volume (ppbV) has been designed and tested with pulsed UV laser. Some design optimization factors such as the optimum cell geometry, buffer gas etc has been proposed. It was found that a cylindrical cell with many acoustic filters considerably dampens the noise level and also argon as a buffer gas improves the photoacoustic signal level and this combination substantially improved the signal to noise ratio and the limit of detection. Ambiguous decline of photo acoustic signal at higher NO2 concentration due to the adsorption of NO2 on the walls of the photoacoustic cells and the dependence of this effect on the buffer gases are also discussed. The PA signal dependence on incident laser energy for three cells was also investigated.
TL;DR: A new simple method for the signal enhancement of laser-induced breakdown spectroscopy using a pulsed buffer gas jet is reported, which enhances the signal up to more than 10 fold by using argon gas jets.
Abstract: We report a new simple method for the signal enhancement of laser-induced breakdown spectroscopy using a pulsed buffer gas jet. The signal is enhanced up to more than 10 fold by using argon gas jets, which are injected through a pulsed nozzle onto the sample area to be analyzed. By synchronizing the buffer gas pulse with the laser pulse and optimizing the spatial arrangements between the gas jet and the sample surface, we have successfully exploited the useful properties of the buffer gas in open atmosphere. The signal-enhancement mechanism in our buffer gas jet has been discussed. Also, applications to various samples (metal, glass, and paper) have been demonstrated.
TL;DR: In this article, a pair of gold-vapor laser (627.8nm) in an oscillator-amplifier configuration was used to investigate the small signal gain, g 0, and saturation intensity, I s, as amplifying parameters, versus pressure at various types of buffer gas.
TL;DR: A new submicron thin cell (STC) filled with Rb and neon gas is developed and comparison of resonant absorption with STC containing pure Rb is provided and a good agreement with theoretical model is observed.
Abstract: A new submicron thin cell (STC) filled with Rb and neon gas is developed and comparison of resonant absorption with STC containing pure Rb is provided. The effect of collapse and revival of Dicke-type narrowing is still observable for the thickness L = λ/2 and L = λ, where λ is a resonant laser wavelength 794 nm (D1 line). For an ordinary Rb cm-size cell with addition of buffer gas, the velocity selective optical pumping/saturation (VSOP) resonances in saturated absorption spectra are fully suppressed if neon pressure > 0.5 Torr. A spectacular difference is that for L = λ, VSOP resonances are still observable even when neon pressure is ≥ 6 Torr. Narrow fluorescence spectra at L = λ/2 allow one to realize online buffer gas pressure monitoring. A good agreement with theoretical model is observed.