Showing papers on "Parametric oscillator published in 1972"
1,008 citations
TL;DR: In this article, the operation of a parametric oscillator phase matched in a GaAs thin-film waveguide is considered, and expressions for parametric gain and oscillation threshold are derived.
Abstract: The operation of a parametric oscillator phase matched in a GaAs thin-film waveguide is considered. Parametric equations of motion for interacting waveguide fields at three frequencies are developed. From these equations we derive expressions for parametric gain and oscillation threshold. A specific orientation of GaAs allows optically smooth cleaved surfaces to form the oscillator cavity. Conditions for which three waveguide modes at three different frequencies can be phase matched are presented for several specific waveguide-substrate structures. These conditions are in each case determined for a wide variety of mode orders, for a laser pump wavelength of 1.06 μ, and for a large range of signal wavelengths. The deviation in thin-film thickness that can be tolerated while maintaining phase matching over a given interaction length is calculated. We find that transverse coupling strength and oscillation threshold powers are widely variable for different phase matched mode order combinations. Oscillator frequency tuning is investigated by first deriving expressions for variations in waveguide parameters required to effect tuning over a specific range and then evaluating these expressions for some of the previously determined phase-matching situations.
63 citations
TL;DR: In this article, the authors extended the steady-state plane-wave theory for the singly resonant parametric oscillator to the case of arbitrary mirror reflectivities using the exact solutions given by Armstrong et al. [3] for the parametric interaction of three traveling waves.
Abstract: Previous steady-state plane-wave theory for the singly resonant parametric oscillator has been extended to the case of arbitrary mirror reflectivities using the exact solutions given by Armstrong et al. [3] for the parametric interaction of three traveling waves. Numerical results are obtained for the efficiency, pump power transmission, optimum output coupling, threshold for the second mode, etc., for parametric oscillators with arbitrary mirror reflectivities and operating under arbitrary power levels. The analysis is also applied to the intracavity-coupled parametric oscillator-upconverter.
49 citations
TL;DR: In this article, an infrared singly resonant parametric oscillator using CdSe as the nonlinear crystal was demonstrated using a Q-switched Nd : YAG laser operating at 1.833 μ as a pump source.
Abstract: We have demonstrated an infrared singly resonant parametric oscillator using CdSe as the nonlinear crystal. The oscillator operates with either a resonant signal near 2.2 μ or resonant idler in the 9.8‐ to 10.4‐μ region. Using a Q‐switched Nd : YAG laser operating at 1.833 μ as a pump source, we have observed thresholds of 550 W and up to 40% conversion efficiency. The angle‐tuned oscillator operates at room temperature with a 2‐cm−1 bandwidth.
48 citations
TL;DR: Stiffened rectangular plates parametric instability under in-plane sinusoidal dynamic forces, using mathematical model with stiffeners as discrete elements as discussed by the authors, using stiffener as discrete element.
Abstract: Stiffened rectangular plates parametric instability under in-plane sinusoidal dynamic forces, using mathematical model with stiffeners as discrete elements
42 citations
TL;DR: Single longitudinal mode operation of an optical parametric oscillator has been achieved using a low loss, mode-matched interferometer as a mode selector to obtain bandwidths of 0.001 cm-1 in the region of 2.5 μm.
36 citations
TL;DR: In this article, an infrared parametric oscillator using proustite and pumped at 1.065 μm has been operated with peak output powers in the kilowatt range.
Abstract: An infrared parametric oscillator using proustite and pumped at 1.065 μm has been operated with peak output powers in the kilowatt range. No significant deterioration of output power was observed after several hours of running at 2 pps. Tuning from 1.82 to 2.56 μm was obtained, limited only by the reflectivity limits of the mirrors used. With careful design, DRO proustite oscillators covering the entire range 1.2–9.5 μm now appear feasible.
29 citations
TL;DR: In this paper, it was shown that a marginal ion sound instability in a plasma behaves in a manner similar to that predicted by a Van der Pol type of nonlinear equation including anharmonic terms.
Abstract: Results are presented which show that a marginal ion sound instability in a plasma behaves in a manner similar to that predicted by a Van der Pol type of nonlinear equation including anharmonic terms. Experiments have been performed in which the system is subjected to an external driving force at the fundamental frequency omega 0, and the subharmonic frequencies, which shows that the instability exhibits characteristics similar to the classical nonlinear phenomena of 'jumps' including the associated hysteresis effect. When the system is driven by a forcing oscillation at the harmonic frequencies 2 omega o or 3 omega o, the instability behaves differently from linear forced resonance, and exhibits a behaviour similar to a parametric oscillator. A theory developed to describe this ion sound instability under these various conditions, is compared with the experimental results, and good agreement is obtained.
25 citations
21 citations
TL;DR: In this paper, the behavior of optically pumped atoms in the oscillating rf field is analized classically in terms of the macroscopic magnetization, in the case that the static magnetic field has components both parallel and perpendicular to the rf fields.
Abstract: Behavior of the optically pumped atoms in the oscillating rf field is analized classically in terms of the macroscopic magnetization, in the case that the static magnetic field has components both parallel and perpendicular to the rf field. The theory predicts that the g -factor is modified by the rf field when the Hanle effect and the parametric resonance take place, and that the effect makes its appearance in the variation of width and maxima of lines of the Hanle effect and the parametric resonance. The modification of the g -factor is also derived by the quantum mechanical treatment. The theoretical predictions are quantitatively verified by the experiments with cesium vapor.
21 citations
01 Jun 1972
TL;DR: In this paper, the response time of an amplitude-controlled harmonic oscillator has been greatly reduced by the use of sampling techniques in the control loop, which has been shown to improve the performance of the oscillator.
Abstract: The response time of an amplitude-controlled harmonic oscillator has been greatly reduced by the use of sampling techniques in the control loop.
Journal Article•
TL;DR: In this article, the spectral and other properties of a ruby laser pumped LiIO 3 pulsed doubly resonant parametric oscillator (DRO) with peak power of 100 kW and 10 percent efficiency were reported.
Abstract: Spectral and other properties of a ruby laser pumped LiIO 3 pulsed doubly resonant parametric oscillator (DRO) are reported. This device is tunable from 1.12 to 1.83 μ with peak powers of 100 kW and 10-percent efficiency. The stability of the DRO is discussed. The output of the DRO was doubled into the 5600- 9150-A range using a second LiIO 3 crystal. Peak second-harmonic powers were 10-15 kW.
TL;DR: In this paper, the spectral and other properties of a ruby laser pumped LiIO 3 pulsed doubly resonant parametric oscillator (DRO) with peak power of 100 kW and 10 percent efficiency were reported.
Abstract: Spectral and other properties of a ruby laser pumped LiIO 3 pulsed doubly resonant parametric oscillator (DRO) are reported. This device is tunable from 1.12 to 1.83 μ with peak powers of 100 kW and 10-percent efficiency. The stability of the DRO is discussed. The output of the DRO was doubled into the 5600- 9150-A range using a second LiIO 3 crystal. Peak second-harmonic powers were 10-15 kW.
TL;DR: In this paper, an efficient extension of the tuning range of a 1.09-1.95 µm parametric oscillator to 0.435-0.975 µm by upconversion and doubling internally to the oscillator cavity was reported.
Abstract: Efficient extension of the tuning range of a 1.09-1.95\mu parametric oscillator to 0.435-0.975\mu by upconversion and doubling internally to the oscillator cavity is reported. Unlike previously studied external mixing, internal upconversion and doubling yielded uniform powers of 30 and 60 kW, respectively, over the entire extended tuning range with an unfocused 2-mm ruby laser pump beam of 750 kW.
TL;DR: In this paper, an optical parametric oscillator with a rhodamine 6G dye laser was reported to operate at a frequency from 0.72-2.6 µm.
Abstract: This correspondence reports operation of an optical parametric oscillator pumped with a rhodamine 6G dye laser. Rapid tuning of the parametric oscillator is achieved by changing the dye wavelength. The spectrum from 0.72-2.6 \mu was scanned.
Patent•
30 Aug 1972
TL;DR: An open ended microwave cavity oscillator comprises a microwave diode forming part of a coaxial center conductor secured to the cavity's base wall, and a tuning rod of low loss dielectric material is threaded into the cavity to capacitively tune the oscillator's frequency.
Abstract: An open ended microwave cavity oscillator comprises a microwave diode forming part of a coaxial center conductor secured to the cavity's base wall. A tuning rod of low loss dielectric material is threaded into the cavity to capacitively tune the oscillator's frequency. A varactor diode is mounted within the center of the tuning rod and is connected between an external supply voltage and ground via a ground wire which projects out of the rod and is bent rearwardly to constitute a coupling loop. The varactor diode is connected to a voltage supply for frequency tuning and modulation of the oscillator output.
TL;DR: An exact solution of the quantum-mechanical problem of the energy spectrum and wave functions of the stationary states of an anisotropic oscillator in a one-dimensional magnetic field has been obtained by using the commutation relations for the components of the operator of the velocity and the operators of the coordinates of the particle as mentioned in this paper.
Abstract: An exact solution of the quantum-mechanical problem of the energy spectrum and wave functions of the stationary states of an anisotropic oscillator in a one-dimensional magnetic field has been obtained by using the commutation relations for the components of the operator of the velocity and the operators of the coordinates of the particle. The results apply for all values of the characteristic frequencies of the oscillator (irrespective of the presence or absence of degeneracy) and for all magnetic field strengths. They can be used to obtain models of the magnetic properties of molecules.
Patent•
19 Jan 1972
TL;DR: In this article, an optically pumped magnetometer utilizing the phenomenom of multiple photon transitions in helium was proposed, where two oscillators of any frequency in an He magnetometer, whose total quantum energy and angular momentum are equivalent to the values required by single-field irradiation, were used.
Abstract: An optically pumped magnetometer utilizing the phenomenom of multiple photon transitions in helium. Multiple transition makes possible the use of two oscillators of any frequency in an He magnetometer, whose total quantum energy and angular momentum are equivalent to the values required by single-field irradiation. A field at frequency f1 is generated by means of a crystalcontrolled oscillator and a field at frequency f2 is generated by a voltage-controlled oscillator such that f1>> f2, whereby a circularly-polarized field may be generated by the crystalcontrolled oscillator, which virtually eliminates the BlochSiegert effect and results in a very stable system. To conserve angular momentum in such a system, the two oscillators have their coils mounted perpendicular to one another.
TL;DR: In this paper, the design and experimental performance of a wide-band K-band parametric amplifier (paramp) for the experimental domestic satellite communication earth station are described, and an optimum idler frequency for a minimum noise temperature is derived taking into account the varactor diode skin effect.
Abstract: The design and experimental performance of a wide-band K-band parametric amplifier (paramp) for the experimental domestic satellite communication earth station are described. An optimum idler frequency for a minimum noise temperature is derived taking into account the varactor diode skin effect. Wide-band paramps with a double-tuned signal circuit are discussed and it is shown that triple-tuned gain characteristics are realizable with this configuration. Finally, an 18-GHz paramp is described, which can be operated from room- to liquid-helium (LHe) temperature, only requiring adjustment of pumping power and bias voltage and using lithium ferrite circulators. Triple-tuned gain characteristics with a bandwidth of 1300 MHz at a gain of 10 dB are obtained using a miniature pill prong packaged varactor.
TL;DR: In this paper, a harmonic oscillator in a uniform, time varying electric field for which an exact solution is easy to obtain using the Magnus expansion for the evolution operator is provided. But the wavefunction of the oscillator is obtained in the adiabatic and impulse limits assuming the field to be switched on in an exponential fashion.
Abstract: When a system of particles in a bound state is placed in an external field the quantum state of the system depends on the manner in which the field is produced. The two limiting cases of interest are the adiabatic and impulse limits. Since the system does not approach a stationary state in either limit, in general, it is necessary to consider solutions of the time dependent Schrodinger equation. An example of this approach is provided by the problem of a harmonic oscillator in a uniform, time varying electric field for which an exact solution is easy to obtain using the Magnus expansion for the evolution operator. This operator contains the position and momentum in a particularly simple way that allows it to be interpreted in terms of position and momentum shifts produced by the field. The wavefunction of the oscillator is obtained in the adiabatic and impulse limits assuming the field to be switched on in an exponential fashion. Results obtained for these two limiting cases are then shown to be independent of the manner in which the field reaches its final steady value.
TL;DR: In this paper, the time-resolved spectra from the output of a doubly resonant parametric oscillator (DRO) pumped by a cw laser are presented.
Abstract: Time‐resolved spectra from the output of a doubly resonant parametric oscillator (DRO) pumped by a cw laser are presented. Single‐cluster operation of the DRO is observed for low pump powers and a simultaneous multicluster operation at higher pump powers. For the multicluster operation, oscillation by higher‐order modes is also detected.
Patent•
21 Apr 1972TL;DR: In this paper, the operation of a microwave oscillator using an avalanche diode operative in the anomalous mode is stabilized by the use of a double pulse, direct current bias signal.
Abstract: The operation of a microwave oscillator using an avalanche diode operative in the anomalous mode is stabilized by the use of a double pulse, direct current bias signal. The double pulse bias signal first triggers the anomalous mode of diode operation with minimum oscillator instability and reduced oscillator output power, thereafter causing the anomalous mode of diode operation to continue without increasing the oscillator instability but increasing the oscillator output power.
TL;DR: In this paper, the enhancement factor of a trigricyne sulphate (TGS) pyroelectric detector is measured as 40 ∼ 50 at the mechanical resonances whose modes are assigned to dilational modes of a rectangular plate vibrator.
Abstract: It is pointed out that responsivity can be improved by mechanical resonances. The enhancement factor of responsivity of a trigricyne sulphate (TGS) pyroelectric detector is measured as 40 ∼ 50 at the mechanical resonances whose modes are assigned to dilational modes of a rectangular-plate vibrator. Also, a pyroultrasonic parametric amplifier is demonstrated, which can show further improvement of responsivity of the pyroelectric detector by amplifying the strain that accompanies pyroelectricity. Gain and an equivalent circuit are derived using a simplified parametrically coupled multimode vibrator model. A pyroultrasonic parametric amplifier using lead zirconate titanate (PZT) ceramic is demonstrated, and an improvement of about 5 dB is shown. Obtaining the gain stability is one of the serious problems of a pyroultrasonic parametric amplifier.
TL;DR: In this article, a computerized optimization technique is employed to provide design values for broad-band parametric amplifiers, and some results of the procedure are presented in Table 1.
Abstract: A computerized optimization technique is employed to provide design values for broad-band parametric amplifiers. Some results of the procedure are presented.
Patent•
22 Feb 1972
TL;DR: In this article, a ladder network of resistors is constructed for frequency determining resistance leg of an oscillator, each of the resistors having a value relationship to each other defined by a specific set of simultaneous equations related to frequency parameters of the oscillator.
Abstract: A frequency determining resistance leg of an oscillator is constructed as a ladder network, each of the resistors having a value relationship to each other defined by a specific set of simultaneous equations related to frequency parameters of the oscillator. The resulting resistor values comprise a ladder network which, when connected to an oscillator through a push button pad, causes oscillation of the oscillator at predetermined frequencies having specific band widths; but when two adjacent push buttons are pushed, oscillation signals are generated at defined out-of-band frequencies.
TL;DR: In this article, a model of the transient behavior of a triply resonated internal optical parametric oscillator (IOPO) was developed to describe the transient behaviour of the IOPO, and the effects of cavity mode pulling and laser medium dispersion on the dynamic response were explored with respect to the exchange of energy between pump wave and signal and idler wave.
Abstract: A model has been developed to describe the transient behavior of the triply resonated internal optical parametric oscillator (IOPO). Pump, signal, and idler fluxes are expressed as Gaussian eigenmodes of the laser and parametric oscillator resonators, and the resulting equations of motion are parameterized in terms of the Boyd‐Kleinman integrals with equal confocal parameters for all waves. Effects of cavity mode‐pulling and laser‐medium dispersion have been included in the analysis. The transient behavior of IOPO devices driven by a cw‐pumped, repetitively Q‐switched Nd:YAG laser medium and using parametric materials of both low and high nonlinearity has been computed. The influence of mode pulling and laser‐medium dispersion on the dynamic response of the IOPO was explored with respect to (i) exchange of energy between pump wave and signal and idler waves, (ii) approach to the steady state, and (iii) operation in the ``efficient'' pulsing regime.
TL;DR: In this article, the authors derived a simple formula for some electrical parameters of ferroelectric film and applied it to a parametric amplifier at frequency 109 Hz with the pump power less than 100 mW.
Abstract: The formula for dependence of the soft mode frequency on the temperature and biasing field has been obtained in a good agreement with known experimental data. The contribution of mechanisms of losses connected with electrostriction and statical fields produced by defects is considered. The simple formula for some electrical parameters of ferroelectric film is derived. Practical applications of ferroelectrics at microwaves are represented by the experiments on parametric amplifier at frequency 109 Hz with the pump power less than 100 mW.
TL;DR: In this paper, a plane-strain analysis of the dynamic stability of an infinitely long cylindrical shell undergoing breathing oscillations in an infinite inviscid fluid medium is presented.
Abstract: A plane‐strain investigation of the dynamic stability of an infinitely long cylindrical shell undergoing breathing oscillations in an infinite inviscid fluid medium is presented. Kinematic nonlinearities of the shell are retained while the fluid is regarded as a linear acoustic medium. A stability criterion which depends strongly upon the acoustic reactance is developed. When the shell is immersed in a fluid, the added mass of the fluid reduces the frequency for parametric resonance. The damping provided by the acoustic resistance proves to be negligible at parametric resonance. The validity of the neglect of kinematic nonlinearities of the fluid is demonstrated by means of an example.