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1 Jan 1980

Volume 51, Issue 1, pp. 1-821

Page 1 of 6 Pages Next Page | Jump to Page

Isotope separation in supersonic molecular beams using rf spectroscopy

Aviv Amirav and Uzi Even

J. Appl. Phys. 51, 1 (1980); http://dx.doi.org/10.1063/1.327409 (6 pages) | Cited 6 times

Online Publication Date: 9 July 2008

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Radiative isotope separation (without lasers) has been achieved using isotopic differences in the rf spectrum of paramagnetic molecules in a supersonic nozzle beam. The combination of molecular‐beam magnetic resonance and supersonic molecular‐beam techniques can be used for isotope separation on a large scale. The principle was demonstrated experimentally for molecular oxygen. The vastly larger isotope spectral differences, the tunability of the spectra by external fields, and the use of the well‐developed technologies are promising starting points for this technique.
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28.60.+s Isotope separation and enrichment

On the possibility of decrease of bending moments in circular coils of toroidal magnets

V. E. Keilin and V. Kh. Shleifman

J. Appl. Phys. 51, 7 (1980); http://dx.doi.org/10.1063/1.327296 (4 pages) | Cited 3 times

Online Publication Date: 9 July 2008

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It is shown that (1) if an angular dimension of the supporting structure is large enough, the so‐called modified D‐shaped coil of toroidal magnet differs slightly from the circular one, (2) with the increase of support angle maximum bending moment in a circular toroidal field coil diminishes rapidly. Thus the realistic choice of support angle can guarantee practically pure tension in circular toroidal field coils.
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28.52.-s Fusion reactors
46.25.-y Static elasticity
74.70.-b Superconducting materials other than cuprates
02.60.Cb Numerical simulation; solution of equations

Raman‐like scattering processes in metastable hydrogenic atoms

Y. Heno, A. Maquet, and R. Schwarcz

J. Appl. Phys. 51, 11 (1980); http://dx.doi.org/10.1063/1.327404 (4 pages) | Cited 3 times

Online Publication Date: 9 July 2008

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Differential and total cross sections for various competing two‐photon processes in metastable 2s hydrogenic atoms are given for several current laser frequencies. Exact calculations are performed within the framework of conventional time‐dependent perturbation theory by using a Sturmian representation of the Coulomb Green’s function. Our results are useful for discussing a recent proposal for obtaining intense vacuum uv light sources from anti‐Stokes Raman scattering.
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33.20.Fb Raman and Rayleigh spectra (including optical scattering)

The rate equations used in irradiation studies

Husam Gurol

J. Appl. Phys. 51, 15 (1980); http://dx.doi.org/10.1063/1.327393 (4 pages) | Cited 3 times

Online Publication Date: 9 July 2008

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The main purpose of this paper is the investigation of the rate equations used in the theories of void nucleation and swelling as well as creep, in situations where random displacement cascades are the major source of point defects. The point‐defect concentrations are described by diffusion equations with random source terms to account for the cascades. Using methods from nuclear reactor kinetic theory and averaging over time, the rate equations are derived. It is seen that the rate equations are valid for computing time and spatially averaged point‐defect concentrations, regardless of the cascade statistics, if the observation time is greater than the mean time between cascade events in the irradiated material. An alternate approach is suggested for studying pulsed systems with short pulse widths.
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34.90.+q Other topics in atomic and molecular collision processes and interactions (restricted to new topics in section 34)
81.90.+c Other topics in materials science (restricted to new topics in section 81)
02.50.Fz Stochastic analysis

Investigation of stray particle loss in deflection magnet region of neutral beam line

J. Kim and M. M. Menon

J. Appl. Phys. 51, 19 (1980); http://dx.doi.org/10.1063/1.327400 (3 pages) | Cited 1 time

Online Publication Date: 9 July 2008

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Separation of residual charged particles from neutral particles is typically made by a deflection magnet in a neutral beam injection line for heating fusion plasmas. Ionization of energetic neutrals and neutralization of energetic ions in the deflection magnet region due to collisions with the background gas molecules result in a finite amount of particles that are only partially deflected, which we call a ’’stray particles loss.’’ Quantitative determination of the stray particle loss has been made from calorimetric data of beam power deposited along a beam line employing a 40‐kV 60‐A hydrogen ion source. The stray particle loss is typically 3–5% of the accelerator power and roughly proportional to the background gas pressure. A simple calculation is shown to be in fair agreement with the measurements.
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29.27.-a Beams in particle accelerators
29.25.-t Particle sources and targets
52.75.Di Ion and plasma propulsion
52.50.Gj Plasma heating by particle beams

Relativistic electron‐beam propagation in vacuum with ion acceleration

Peter L. Taylor

J. Appl. Phys. 51, 22 (1980); http://dx.doi.org/10.1063/1.327414 (8 pages) | Cited 8 times

Online Publication Date: 9 July 2008

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A self‐pinched relativistic electron beam is injected through a thin foil into vacuum with no externally applied magnetic field. The beam is observed to propagate at currents well above the space‐charge‐limiting current (∼3 kA) but limited to the Alfven current (∼30 kA). Propagation results from charge neutralization of the beam by ions accelerated out of the anode plasma as confirmed by various ion diagnostics. Ions are collectively accelerated to greater than the electron energy. The experimental results are in qualitative agreement with a one‐dimensional time‐dependent computer simulation.
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41.75.Fr Electron and positron beams
29.20.-c Accelerators

Coupling of spherical‐surfaced LED and spherical‐ended fiber

Osamu Hasegawa, Ryosuke Namazu, Masayuki Abe, and Yoshikazu Tōyama

J. Appl. Phys. 51, 30 (1980); http://dx.doi.org/10.1063/1.327372 (7 pages) | Cited 9 times

Online Publication Date: 9 July 2008

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The coupling of a spherical‐surfaced LED and a spherical‐ended fiber is analyzed using a model in which a light source and an aperture stop are on the anterior and posterior focal planes, respectively. The launching efficiency is defined as the ratio of the power launched into a fiber to the optical power generated in the LED. The efficiencies for step‐ and graded‐index fibers are derived. Maximum efficiency can be obtained when d0=dc, where d0 is the emitting diameter and dc is the critical diameter defined by the focal length and the critical angle of the fiber. When d0?dc, the ratio χ of improvement in the efficiency for a spherical‐surfaced LED to that for a flat LED is approximately proportional to the square of the lateral magnification β, which is the image diameter divided by d0. χ?β2 is confirmed experimentally with couplings using spherical‐surfaced and flat LED’s.
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42.79.Sz Optical communication systems, multiplexers, and demultiplexers
85.60.Jb Light-emitting devices
42.81.-i Fiber optics

Pulse amplification in high‐power iodine laser

J. C. Farcy, M. Huguet, J. C. Guyot, D. Savry, and H. Guillet

J. Appl. Phys. 51, 37 (1980); http://dx.doi.org/10.1063/1.327382 (3 pages)

Online Publication Date: 9 July 2008

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Amplification of 0.6‐, 1.6‐, and 100‐ns pulses has been measured in a test amplifier up to 3 atm. total pressure and a small signal gain ranging from 5.5 to 19 dB. A simple model based on a Frantz and Nodvick formulation provides good agreement with the experimental results for 0.6–1.6‐ns pulse duration and can be useful for an iodine laser system design.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.55.-f Lasers

Raman‐induced Kerr effect with nonmonochromatic waves

Niloy K. Dutta

J. Appl. Phys. 51, 40 (1980); http://dx.doi.org/10.1063/1.327388 (3 pages)

Online Publication Date: 9 July 2008

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We discuss the theory of Raman‐induced Kerr effect (RIKE) when excited by nonmonochromatic waves. The maxima and minima of the lineshape are shifted farther apart when pumped by linearly polarized nonmonochromatic waves. The shift varies linearly with the sum of the pump and probe linewidths. Certain other features are also predicted in agreement with experimental results.
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42.65.Dr Stimulated Raman scattering; CARS
42.65.Es Stimulated Brillouin and Rayleigh scattering
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
42.62.-b Laser applications

GaInAsP/InP planar stripe lasers prepared by using sputtered SiO2 film as a Zn‐diffusion mask

Kunishige Oe, Seigo Ando, and Koichi Sugiyama

J. Appl. Phys. 51, 43 (1980); http://dx.doi.org/10.1063/1.327340 (7 pages) | Cited 4 times

Online Publication Date: 9 July 2008

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The dependence of lasing characteristics on stripe width in GaInAsP/InP double‐heterostructure planar stripe lasers, prepared by using sputtered SiO2 film as a Zn‐diffusion mask, was investigated. The lasers of 10‐, 15‐, and 20‐μm‐wide stripes operated in a fundamental‐transverse mode with more than 20% differential quantum efficiencies per facet, while the 5‐μm‐wide stripe lasers operated in a multi‐transverse‐mode even just above threshold. The threshold current of 5‐μm‐wide stripe lasers increased greatly, and the lasing wavelengths shifted to shorter than those of stripe lasers with larger stripe widths. The 15‐μm‐wide stripe lasers showed good mode characteristics to operate in a fundamental‐transverse mode up to the output power of 22 mW per facet and in a single longitudinal mode over a wide range of currents. The cause of this dependence of lasing characteristics on stripe width was discussed, and it was assumed that the Zn diffusion into the stripe region using a sputtered SiO2 mask is most responsible for the dependence.
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42.55.Px Semiconductor lasers; laser diodes
85.60.Jb Light-emitting devices
78.30.Hv Other nonmetallic inorganics

The effects of focusing in the three‐frequency parametric upconverter

Shekhar Guha and Joel Falk

J. Appl. Phys. 51, 50 (1980); http://dx.doi.org/10.1063/1.327353 (11 pages) | Cited 16 times

Online Publication Date: 9 July 2008

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This paper extends the theory of parametric upconversion to describe the mixing of two focused optical beams with unequal confocal parameters. The results of this paper have greatest applicability when focusing of one input beam is limited by physical constraints, e.g., damage. The effects of phase matching, walk‐off, and diffraction are treated herein. The analysis shows that if the beams have fixed confocal parameters b1 and b2, optimum mixing generally occurs with b2≠b1. If both confocal parameters can be arbitrarily chosen, maximum efficiency occurs with b1=b2= (crystal length)/2.84 in the absence of Poynting vector walk‐off, and with b1≠b2 in the presence of walk‐off. For weak focusing upconversion efficiency is written in a closed form which shows explicitly the effect of walk‐off.
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63.10.+a General theory
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation

Microwave generation by intense relativistic electron beams propagating in a circular waveguide

B. Etlicher, A. Huetz, J. M. Buzzi, P. Haldenwang, and D. Lequeau

J. Appl. Phys. 51, 61 (1980); http://dx.doi.org/10.1063/1.327317 (7 pages) | Cited 5 times

Online Publication Date: 9 July 2008

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The stability of circular waveguide modes perturbed by a relativistic electron beam is investigated. The electron beam propagates along the waveguide and is guided by an applied uniform axial magnetic field. The electron beam is represented by a distribution of rigid rotators all having the same energy and Larmor radius rL with their guiding centers centered on a circle or radius Rb around the guide axis. Numerical results are presented giving a general view of the competition between synchronous and cyclotron instabilities for TM and TE modes as a function of rL and Rb.
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84.40.Ik Masers; gyrotrons (cyclotron-resonance masers)
84.40.Fe Microwave tubes (e.g., klystrons, magnetrons, traveling-wave, backward-wave tubes, etc.)
52.27.Ny Relativistic plasmas
41.60.-m Radiation by moving charges

Optical and microwave instabilities in injection lasers

B. W. Hakki

J. Appl. Phys. 51, 68 (1980); http://dx.doi.org/10.1063/1.327326 (6 pages) | Cited 11 times

Online Publication Date: 9 July 2008

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We find that the onset of instability in many GaAs DH lasers that are capable of self‐induced modulation is always preceded by the strong emission of noise. The longitudinal optical‐mode width is fairly narrow, typically 0.1–0.3 Å, when the optical power contains noise. It is only after the optical power exhibits coherent self‐induced modulation that the apparent longitudinal mode width increases to 1–2 Å. This apparent increase in longitudinal mode width is attributed to a wavelength that changes periodically (sinusoidally, for small signals) with time. The wavelength oscillation is due to variations in refractive index brought about by oscillations in the carrier concentration. The implication is that in these lasers, the instantaneous longitudinal optical mode width is relatively narrow regardless of the temporal instability of the light output. In addition, it is shown analytically that there is a critical noise level above which a laser becomes unstable, i.e., exhibits coherent self‐induced modulation.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
42.60.Fc Modulation, tuning, and mode locking
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Active remote sensing of random media

M. Zuniga and J. A. Kong

J. Appl. Phys. 51, 74 (1980); http://dx.doi.org/10.1063/1.327335 (6 pages) | Cited 17 times

Online Publication Date: 9 July 2008

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Analytical results for the bistatic scattering coefficients and the backscattering cross sections have been derived for active remote sensing of earth terrain with the model of bounded random media which accounts for volume‐scattering effects. It is found that as a result of the effect of the second boundary, the horizontally polarized return σhh can be greater than the vertically polarized return σvv, whereas for a half‐space random medium σvv is always greater than σhh. We illustrate by matching the theoretical results with experimental data collected from vegetation field.
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42.25.Dd Wave propagation in random media
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing

Dependence of the infrared output power of a hollow‐cathode Cu+ laser on He and Ar pressures

H. J. Eichler and W. Wittwer

J. Appl. Phys. 51, 80 (1980); http://dx.doi.org/10.1063/1.327301 (4 pages) | Cited 4 times

Online Publication Date: 9 July 2008

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The dependence of the infrared laser power produced by a hollow‐cathode copper ion laser on the He and Ar pressure is reported. An argon partial pressure of 1 mbar is found to be optimum and nearly independent of the helium partial pressure and discharge current. The optimum He pressure is about 25 mbar, dependent on the discharge current. A simple rate equation model is given and compared to the experimental results.
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42.55.-f Lasers
42.55.Lt Gas lasers including excimer and metal-vapor lasers
34.70.+e Charge transfer
42.60.By Design of specific laser systems

Two‐photon resonant four‐wave parametric amplification

Niloy K. Dutta

J. Appl. Phys. 51, 84 (1980); http://dx.doi.org/10.1063/1.327306 (6 pages) | Cited 1 time

Online Publication Date: 9 July 2008

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Four‐wave parametric amplification is discussed when the incident pump frequency is close to a two‐photon resonant transition in the material. Expressions for the amplification factor are obtained both under steady‐state and pulsed excitation and also for a nonmonochromatic pump. For ultrashort‐pulse excitation an ’’energy theorem’’ is derived and discussed. In steady state, expressions for optimum frequency and intensity are obtained. The amplification factor under broad‐band excitation decreases with increasing pump linewidth.
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42.65.Dr Stimulated Raman scattering; CARS
42.65.Es Stimulated Brillouin and Rayleigh scattering
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Optically induced crosstalk in LiNbO3 waveguide switches

R. V. Schmidt, P. S. Cross, and A. M. Glass

J. Appl. Phys. 51, 90 (1980); http://dx.doi.org/10.1063/1.327307 (4 pages) | Cited 20 times

Online Publication Date: 9 July 2008

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Observations of optically induced crosstalk drift in LiNbO3 waveguide directional coupler switches at 0.633‐ and 1.06‐μm wavelengths are reported. At 1.06 μm, crosstalk has been observed to remain below −25 dB for optical powers of 1 mW. The drift at 0.633 μm is explained in terms of the photorefractive effect of LiNbO3.
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42.79.Gn Optical waveguides and couplers
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Effects of chemical kinetics of the performance of the atomic iodine laser system

George A. Fisk and Frank K. Truby

J. Appl. Phys. 51, 94 (1980); http://dx.doi.org/10.1063/1.327308 (8 pages) | Cited 1 time

Online Publication Date: 9 July 2008

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Model calculations show that chemical reactions which take place in the active medium of a photolytically pumped iodine laser limit the efficiency with which pump photons are utilized and convert significant amounts of the starting material RI to the unwanted by‐products R2 and I2. Laser‐ and rf‐discharge‐based methods for regenerating starting materials from by‐products are evaluated experimentally. For economical operation of large iodine laser systems, CF3I is presently the best starting material, and a pulsed rf‐discharge technique is presently the best one for chemical regeneration. The absorbed energy required to regenerate one CF3I molecule using pulsed rf‐discharge techniques is 5.8 eV.
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42.60.By Design of specific laser systems
82.40.-g Chemical kinetics and reactions: special regimes and techniques
82.50.-m Photochemistry
52.80.Pi High-frequency and RF discharges

Influence of proton‐stripe realization process on the luminescence properties of (AlGa)As double heterostructures

E. V. K. Rao and N. Duhamel

J. Appl. Phys. 51, 102 (1980); http://dx.doi.org/10.1063/1.327401 (7 pages) | Cited 4 times

Online Publication Date: 9 July 2008

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Photoluminescence (PL) measurements using two different incident photon energies (one, higher than both GaAs and AlxGa1−xAs band‐gap energies: indirect excitation; the other, higher than GaAs band‐gap energy but less than Ga1−xAlxAs band‐gap energy: direct excitation) have been conducted on proton‐striped double heterostructures (DH) for cw lasers. These measurements performed inside and outside the stripe regions gave the following results: the luminescence from the regions inside the stripe, when measured under indirect excitation conditions is shown to be affected by the proton bombardment; also a simple heat treatment of these layers is found to restore this luminescence to a large extent. Some experimental evidence assuming the presence of nonradiative centers localized in the neighborhood of P‐AlxGa1−xAs (confinement layer) and p‐GaAs (active layer) heterointerface is presented and discussed.
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42.55.Px Semiconductor lasers; laser diodes
78.60.-b Other luminescence and radiative recombination

Recombination lasing in a magnetoplasmadynamic arcjet

E. M. Campbell, R. G. Jahn, W. F. von Jaskowsky, and K. E. Clark

J. Appl. Phys. 51, 109 (1980); http://dx.doi.org/10.1063/1.327402 (9 pages) | Cited 12 times

Online Publication Date: 9 July 2008

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The plasmadynamic recombination laser concept is verified experimentally in a high‐power quasisteady MPD arcjet operating at 4 kA and 12 g/sec of argon. Measurements of the spatial variation of electron temperature, electron density, and population densities in the arc exhaust flow confirm that inverted populations of the 4p to 4s Ar II transitions are established by collisional‐radiative recombination of the Ar III ion. Using an optical cavity aligned transversely to the flow, recombination lasing of seven such transitions, 5145, 4880, 4764, 4727, 4658, 4579, and 4545 Å, is observed spectrophotograpically and photoelectrically over the entire 1‐msec discharge.
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42.60.By Design of specific laser systems
52.30.-q Plasma dynamics and flow
34.90.+q Other topics in atomic and molecular collision processes and interactions (restricted to new topics in section 34)
42.55.Lt Gas lasers including excimer and metal-vapor lasers

Simultaneous stimulated Raman scattering and optical frequency mixing employing a three‐mirror Raman configuration

E. O. Ammann

J. Appl. Phys. 51, 118 (1980); http://dx.doi.org/10.1063/1.327403 (5 pages) | Cited 1 time

Online Publication Date: 9 July 2008

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The simultaneous occurrence of stimulated Raman scattering and optical frequency mixing in LiIO3 at kHz PRF’s (pulsed repetition frequency) has previously been investigated using a two‐mirror internal Raman configuration. These simultaneous processes produce multiple visible outputs that are selectable by rotating the LiIO3 crystal. In this paper, the same simultaneous processes are investigated using a three‐mirror configuration. It is found that the three‐mirror configuration yields smaller average visible output powers, but larger peak powers, than the corresponding two‐mirror configuration.
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42.65.Dr Stimulated Raman scattering; CARS
42.65.Es Stimulated Brillouin and Rayleigh scattering
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

The hollow‐cathode helium‐fluorine laser

J. K. Crane and J. T. Verdeyen

J. Appl. Phys. 51, 123 (1980); http://dx.doi.org/10.1063/1.327405 (7 pages) | Cited 1 time

Online Publication Date: 9 July 2008

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It is possible to obtain uniform stable long‐pulse excitation (?100 μs) in gas mixtures involving highly electronegative constituents (SF6, CCl4, NF3, and I2). Such a system was used to investigate the atomic fluorine laser. In the hollow cathode, lasing on fluorine transitions in the doublet system lasted for up to 80 μs with no signs of the self‐termination as reported previously in positive‐column devices. The excitation process of the laser appears to depend heavily upon the fluorine donor utilized. For instance, a single‐step process is involved when NF3 is used whereas a two‐step process is evident for SF6. The details will be discussed.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.By Design of specific laser systems

Kinetic modeling of rotational nonequilibrium in chemical lasers. A comparison of three models applied to the Cl2/HI/He system

Yakir Reuven, Avinoam Ben‐Shaul, and Michael Baer

J. Appl. Phys. 51, 130 (1980); http://dx.doi.org/10.1063/1.327406 (12 pages)

Online Publication Date: 9 July 2008

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In this study three theoretical models which yield the temporal evolution of photon densities and population levels for a pulsed chemical laser are compared. The models are applied to the Cl2/HI/He chemical laser system. The simplest one is the well‐known Boltzmann equilibrium model (BEQM) which assumes instantaneous rotational equilibrium throughout the lasing period. This assumption is removed in the detailed rotational nonequilibrium model (DRNM) which follows the time development of each vib‐rotational population level separately. A third model, recently introduced by Baer, Top, and Alfassi, is an approximate rotational relaxation model (ARRM) which represents the rotational distribution in each vibrational level as a linear combination of three known functions with time‐dependent coefficients. The main conclusions are as follows: (1) The BEQM is inadequate for providing the properties of a laser operating under low and intermediate inert‐gas pressures. It can serve at most to derive an upper bound for the actual laser performance. (2) The ARRM provides very good estimates of total laser energy and efficiency as well as of more detailed properties, such as band intensities and the temporal behavior of the vibrational populations, for a wide range of pressures. (3) The use of the DRNM cannot be avoided if fine details, such as spectral distribution of output energy or rotational energy profiles, are required.
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42.55.Ks Chemical lasers
82.40.Bj Oscillations, chaos, and bifurcations
82.20.Wt Computational modeling; simulation

Surface wave scattering from elliptical cracks for failure prediction

B. R. Tittmann, O. Buck, L. Ahlberg, M. De Billy, F. Cohen‐Tenoudji, A. Jungman, and G. Quentin

J. Appl. Phys. 51, 142 (1980); http://dx.doi.org/10.1063/1.327407 (9 pages) | Cited 11 times

Online Publication Date: 9 July 2008

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The scattered radiation patterns from surface cracks irradiated by acoustic surface waves are interpreted to provide estimates of crack length and aspect ratio, geometric crack parameters needed to enable failure prediction. The technique is demonstrated for circular and elliptical cracks as small as 100 μm in depth with an accuracy of about 10%. The key features are the positions and spacing of peaks and nulls in angular frequency dependence of scattered surface wave intensity. A simple model based on optical diffraction theory is demonstrated on cracks in commercial hot‐pressed silicon nitride studied at 100 MHz and on spark‐eroded slots in commercial aluminum studied at 2–10 MHz. The results are used to calculate the stress intensity factors and to describe the direction of crack propagation for a variety of real and simulated cracks. Implications of the technique with respect to crack closure and effects of stress and time are also discussed.
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43.20.Fn Scattering of acoustic waves
68.35.Gy Mechanical properties; surface strains
68.35.Iv Acoustical properties

Interaction of magnetoelastic wave with drifting carriers in a ferrite‐semiconductor hybrid structure

Toshinobu Yukawa, Jun‐ichi Ikenoue, Shigeru Shingai, and Kenji Abe

J. Appl. Phys. 51, 151 (1980); http://dx.doi.org/10.1063/1.327408 (10 pages) | Cited 2 times

Online Publication Date: 9 July 2008

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The interaction of horizontally polarized shear (SH) magnetoelastic waves with drifting carriers is analyzed in a ferrite‐semiconductor hybrid structure. Wave amplification occurs when the drift velocity of carriers exceeds the phase velocity of the wave. The more magnetostatic the wave, the stronger the interaction of the wave with carriers. The imaginary part of the wave number increases linearly as the drift field (or the drift velocity of carriers) increases, is proportional to the conductivity of the semiconductor, and takes a maximum value in the vicinity of the cutoff frequency of ferrite‐air (FA) modes. These results are supported by an approximate solution for the imaginary parts of the wave numbers for the magnetoelastic surface wave interacting with a semiconductor. It is clear that elastic waves and carriers can interact through the medium of the magnetostatic surface wave by means of magnetoelastic coupling and interaction between the magnetostatic surface wave and carriers.
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43.35.-c Ultrasonics, quantum acoustics, and physical effects of sound
85.70.Ge Ferrite and garnet devices
84.30.Le Amplifiers
41.20.Jb Electromagnetic wave propagation; radiowave propagation
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