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Applied Physics B: Lasers and Optics (09462171)77(5)pp. 509-513
A compact mid-infrared (MIR) laser system is described applying two single mode diode-lasers as pump and signal sources to generate difference-frequency radiation in AgGaS2. A spectral tuning range of 71.5 cm-1 between 4.9-5.1 μm with an output power of 100 nW and linewidth of 1.2 × 10-2 cm-1 (3.6 GHz) for the DFG laser system is obtained by mode behavior improvement of the pump source using an external short-cavity. The performance of such an external short-cavity MIR-DFG laser spectrometer is demonstrated by recording the fundamental absorption spectra of carbon monoxide (12C16O) and nitric oxide (14N16O) in a 10 cm long cell in order to estimate line-broadening coefficients of CO and NO molecules, which are of general interest in combustion diagnostics.
Proceedings of SPIE - The International Society for Optical Engineering (1996756X)5249pp. 249-260
A systematic design method for quasi-symmetrical wide angle systems is presented. The method starts with thin lens predesign of half of the system using most available glasses. The aperture stop position is determined for reducing astigmatism and the system is made symetrical about it for eliminating Coma, Lateral colour and Distortion. Finally the system is optimized using Eikonal software for infinite conjugate.
Journal of Physics B: Atomic, Molecular and Optical Physics (09534075)37(16)pp. 3321-3338
The Faddeev-Watson-Lovelace (FWL) treatment, in a second-order approximation, and an active electron model have been applied to calculate the single-electron capture differential cross sections from K-, L- and M-shells of many-electron atoms by protons at medium and high (but non-relativistic) impact energies. The radial part of the wavefunction for the active electron was obtained by constructing suitable bases from merging hyperbolic cosine functions with Slater-type radial ones. Converting the Schrödinger-like equation obtained from Hartree-Fock theory gives the effective potential, which is experienced by the active electron in the target atom. A simple analytic radial function composed of a Coulomb and a Yukawa potential was fitted to the effective potential. Near-the-shell two-body T-matrices, electronic-nuclear and inter-nuclear partial amplitudes are calculated to obtain the electron capture differential cross sections between various shells of the target atom and the ground state of atomic hydrogen formed, Theoretical results are compared with the available experimental data on helium, neon and argon atoms at different energies.
Progress of Theoretical Physics (13474081)112(5)pp. 797-809
Considering a simple generalization of the (p, q)-deformed boson oscillator algebra, which leads to a two-parameter deformed bosonic algebra in an infinite dimensional subspace of the harmonic oscillator Hilbert space without first finite Fock states, we establish a new harmonic oscillator realization of the deformed boson operators based on the Bogoliubov (p, q)-transformations. We obtain exact expressions for the transformation coefficients and show that they depend on arbitrary functions of p and q which can be interpreted as the parameters of the (p, q)-deformed GL(2, C) group. We also examine the existence and structure of the corresponding deformed Fock-space representation for our problem.
Proceedings of SPIE - The International Society for Optical Engineering (1996756X)5249pp. 740-745
The different methods of optical systems' optimization such as Newton and Least Squares along with their modification are discussed. Monte-Carlo technique as an statistical method which can overcome the shortcoming of those classic methods (such as the rate of convergence, the possibility of finding the overall minimum and avoiding local minima) is presented and compared with the other ones. An numerical example is presented to verify the method.
Wondraczek, L., Heide, G., Frischat, G.H., Khorsandi, A.R., Willer, U., Schade w., W.
Glass Science and Technology (09467475)77(2)pp. 68-76
Laser spectroscopic diagnostics of combustion species at elevated temperature has shown considerable progress during the last years and decades. Particularly, techniques of mid-infrared absorption spectroscopy using fundamental rotational/vibrational transitions offer potentially great sensitivity and selectivity for combustion control. However, applications are still limited to mostly laboratoryscale investigations, which is mainly due to drawbacks of light sources and beam guidance materials. On the other hand, many efforts are made to facilitate industrial application. In this context, the relevance of mid-infrared absorption spectroscopy for in situ monitoring of minor species in glass melting furnaces is obvious, too. The present paper gives a general review of available techniques and their impact on emission diagnostics in the glass industry, considering conventional as well as emerging light sources, detectors, peripheral devices and spectroscopic techniques.
Wondraczek, L., Heide, G., Frischat, G.H., Khorsandi, A.R., Willer, U., Schade w., W.
Glass Science and Technology (09467475)77(3)pp. 131-136
Emerging techniques of mid-infrared absorption spectroscopy offer potentially great sensitivity and selectivity for combustion control and emission monitoring. Because of that, a difference frequency based mid-infrared absorption spectrometer has been considered for application in the glass industry. Based on preliminary tests within laboratory conditions, a spectrometer which operates at wavelengths around 5 μm was applied to online monitoring of the atmosphere of a gas fired glass melting furnace. The CO concentration was measured in order to demonstrate the feasibility of a mid-infrared absorption spectrometer for process control in the glass industry. A series of measurements was performed in situ as well as crossing the recuperator entry, resulting in general advice on the construction of a prototype device.
Journal of Physics A: Mathematical and General (03054470)37(9)pp. 3225-3240
In this paper, we introduce a new family of photon-added as well as photon-depleted q-deformed coherent states related to the inverse q-boson operators. These states are constructed via the generalized inverse q-boson operator actions on a newly introduced family of q-deformed coherent states (Quesne C 2002 J. Phys. A: Math. Gen. 35 9213) which are defined by slightly modifying the maths-type q-deformed coherent states. The quantum statistical properties of these photon-added and photon-depleted states, such as quadrature squeezing and photon-counting statistics, are discussed analytically and numerically in the context of both conventional (nondeformed) and deformed quantum optics.
Canadian Journal of Physics (00084204)82(8)pp. 623-646
By introducing a generalization of the (p, q)-deformed boson oscillator algebra, we establish a two-parameter deformed oscillator algebra in an infinite-dimensional subspace of the Hubert space of a harmonic oscillator without first finite Fock states. We construct the associated coherent states, which can be interpreted as photon-added deformed states. In addition to the mathematical characteristics, the quantum statistical properties of these states are discussed in detail analytically and numerically in the context of conventional as well as deformed quantum optics. Particularly, we find that for conventional (nondeformed) photons the states may be quadrature squeezed in both cases Q = pq < 1, Q = pq > 1 and their photon number statistics exhibits a transition from sub-Poissonian to super-Poissonian for Q < 1 whereas for Q > 1 they are always sub-Poissonian. On the other hand, for deformed photons, the states are sub-Poissonian for Q > 1 and no quadrature squeezing occurs while for Q < 1 they show super-Poissonian behavior and there is a simultaneous squeezing in both field quadratures.
Progress of Theoretical Physics (13474081)112(5)pp. 811-829
We construct a family of deformed boson coherent states associated with deformed Bogoliubov (p, q)-transformations in an infinite dimensional subspace of the harmonic oscillator Hilbert space without first finite Fock states. We investigate their over-completeness and show that they allow the resolution of unity in the form of an ordinary integral (for Q = pq < 1) or a generalized Q-deformed one (for Q = pq > 1). We study in detail analytically and numerically some of the geometrical and physical properties of these deformed coherent states in the context of deformed quantum optics. In particular, we show that for Q > 1 they exhibit sub-Poissonian statistics and no quadrature squeezing occurs while for Q < 1 their photon number statistics is super-Poissonian and there is a simultaneous squeezing in both field quadratures (double squeezing). Additionally, by a natural extension, we construct the corresponding multi-photon deformed coherent states and investigate their properties.
Journal of Physics A: Mathematical and General (03054470)37(21)pp. 5649-5660
We establish some of the properties of the states interpolating between number and coherent states denoted by |n〈λ; among them are the reproduction of these states by the action of an operator-valued function on |n〈 (the standard Fock space) and the fact that they can be regarded as f -deformed coherent bound states. In this paper we use them as the basis of our new Fock space which in this case is not orthogonal but normalized. Then by some special superposition of them we obtain new representations for coherent and squeezed states in the new basis. Finally the statistical properties of these states are studied in detail.
Journal of Physics A: Mathematical and General (03054470)37(15)pp. 4407-4422
Starting with the canonical coherent states, we demonstrate that all the so-called nonlinear coherent states, used in the physical literature, as well as large classes of other generalized coherent states, can be obtained by changes of bases in the underlying Hubert space. This observation leads to an interesting duality between pairs of generalized coherent states, bringing into play a Gelfand triple of (rigged) Hubert spaces. Moreover, it is shown that in each dual pair of families of nonlinear coherent states, at least one family is related to a (generally) non-unitary projective representation of the Weyl-Heisenberg group, which can then be thought of as characterizing the dual pair.
Journal of Physics A: Mathematical and General (03054470)37(33)pp. 8111-8127
Considering some important classes of generalized coherent states known in the literature, we demonstrated that all of them can be created via conventional methods, i.e. the 'lowering operator eigenstate' and the 'displacement operator' techniques using the 'nonlinear coherent states' approach. As a result we obtained a 'unified method' to construct a large class of coherent states which have already been introduced by different prescriptions.
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers (13474065)43(2)pp. 611-620
In this paper, a detailed theoretical treatment of the three dimensional photothermal deflection, under modulated cw excitation, is presented for a three layer system (backing-solid sample-fluid). By using a technique based on Green's function and integral transformations we find the explicit expressions for laser induced temperature distribution function and the photothermal deflection of the probe beam. Numerical analysis of those expressions for certain solid samples shows that the laser induced temperature of the sample surface, the effective thermal length and the deflection signal and its width decrease with increasing modulation frequency. Furthermore, increasing the diffusivity/conductivity of solid sample results in a decrease in the deflection signal intensity and slight increase in the signal width. Finally, we find that the focal length of the photothermal lens in normal direction is much greater than that of in tangential direction.
A new type of noised-induced phase transitions that should occur in systems of elements with motivated behavior is considered. By way of an example, a simple oscillatory system {x, ν = ẋ} with additive white noise is analyzed numerically. A chain of such oscillators is also studied in brief.
Off-the-shell anomalous factors of the two-body Coulomb transition matrices appear in the integral form of the Faddeev second-order nuclear-electronic amplitude, for proton-hydrogen charge transfer scattering in a typical nlm → n′l′m′ transition. A symmetric-impulse approximation (SIA) is applied to eliminate these factors and an induction method is proposed to analytically calculate the remaining integrals. The nuclear-electronic amplitude is derived for the general case, and for totally symmetric collisions, in terms of generalized hypergeometric functions of two variables, F 4, and of one variable, 3 F 2, respectively. The angular distribution of the second-order nuclear-electronic charge transfer amplitude shows the Thomas mechanism as a peak or a hump for symmetric and asymmetric collisions. There also exists a peak in the forward angular distribution of the second-order nuclear-electronic amplitude, which partly cancels the kinematic peak in the angular distribution of the charge transfer differential cross sections.
