1. |
CRYSTALLIZATION OF AMORPHOUS ANTIMONY FILMS PREPARED BY VACUUM EVAPORATION |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 277-279
Kanwar Bahadur,
K. L. Chaudhary,
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摘要:
Antimony films in the thickness range of 50 to 250 Å prepared by vacuum evaporation on single crystal KCL substrates at room temperature show an amorphous structure, which changes readily to the crystalline form on exposure to a 40–100‐kV electron beam of moderate intensity in the electron microscope. At the nucleation stage thin films show a random orientation on crystallization, whereas thicker, nearly continuous films assume a single crystalline orientation, with (111)metal‖(001)KCl.
ISSN:0003-6951
DOI:10.1063/1.1652998
出版商:AIP
年代:1969
数据来源: AIP
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2. |
A MO¨SSBAUER RESONANCE EFFECT STUDY USING A BACKSCATTER GEOMETRY |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 279-282
R. N. Ord,
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摘要:
A Mo¨ssbauer backscatter system has been designed which is capable of 130% resonance effect for a rolled foil stainless‐steel sample having an elliptical‐shaped scatter area of 6.46 in.2. This effect is a function of the surface area of the sample and the energy of the detected photon. For a sample surface area greater than 0.5 in.2, the 14.4‐keV &ggr; ray is the most efficient. This system is significant for nondestructive testing because sampling times are decreased to minutes.
ISSN:0003-6951
DOI:10.1063/1.1652999
出版商:AIP
年代:1969
数据来源: AIP
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3. |
EFFECTS OF DIFFUSION ON THE SATURATION INTENSITY OF A CO2LASER |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 282-284
David C. Smith,
John H. McCoy,
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摘要:
The power and gain capabilities of a CO2laser are dependent upon the saturation intensity of the laser media. Saturation intensities reported in the literature range from 22 to 100 W/cm2for seemingly similar laser discharge tube bores, currents, gas flow rates, and gas mixtures. Measurements of saturation intensities between 7.5 and 57 W/cm2in a CO2laser amplifier indicate that this parameter is inversely related to the radius of the amplified beam. A significant increase in saturation intensity for small beam radii is attributed to diffusion of excited CO2molecules into the beam. The experimental results are in qualitative agreement with a simplified derivation of a relation governing the saturation intensity which includes molecular diffusion. This effect can result in a serious overestimate of the capabilities of a large beam laser system designed with saturation intensities obtained from small diameter probe beams.
ISSN:0003-6951
DOI:10.1063/1.1653000
出版商:AIP
年代:1969
数据来源: AIP
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4. |
TIME‐AVERAGED HOLOGRAPHY WITH TRIANGULAR PHASE MODULATION OF THE REFERENCE WAVE |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 285-287
Franc¸ois M. Mottier,
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摘要:
It is shown that the large differences of the peak fringe intensities in the reconstruction of time‐averaged holograms may be reduced by synchronous triangular phase modulation of the reference wave. As a by‐product, portions of the object vibrating in the same phase are revealed. Optical noise in the reconstruction is low so that the useful amplitude range in vibration analysis is significantly extended by the method described.
ISSN:0003-6951
DOI:10.1063/1.1653001
出版商:AIP
年代:1969
数据来源: AIP
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5. |
ON THE PHASE CHARACTERISTICS AND COMPRESSION OF PICOSECOND PULSES |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 287-290
Robert A. Fisher,
J. A. Fleck,
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摘要:
It is pointed out that published data on the compression of mode‐locked Neodymium‐glass laser pulses do not require the pulse to have a predominantly positive frequency sweep. It is shown that a random pulse carrier phase function, for example, can account for published experimental observations.
ISSN:0003-6951
DOI:10.1063/1.1653002
出版商:AIP
年代:1969
数据来源: AIP
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6. |
DIELECTRIC CONSTANT OF AN ELECTRON‐FREE T1+I−PLASMA |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 290-292
P. Davidovits,
J. L. Hirshfield,
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摘要:
Measurements are reported of the frequency‐dependent complex impedance of a capacitor filled with thallium iodide vapor, photodissociated into T1+and I−to form an electron‐free plasma. Ion concentration and collision frequency are inferred using the cold plasma dielectric constant.
ISSN:0003-6951
DOI:10.1063/1.1653003
出版商:AIP
年代:1969
数据来源: AIP
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7. |
TEMPERATURE DEPENDENCE OF THE ENERGY RELAXATION TIME INn‐InSb |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 292-294
J. J. Whalen,
C. R. Westgate,
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摘要:
The energy relaxation time &tgr;einn‐InSb for the temperature range 1.5 to 20°K has been measured directly in a heterodyne experiment at 69 GHz. A comparison of experimental values for &tgr;ewith theoretical values calculated for a degenerate electron gas yields a deformation potential constant and a piezoelectric potential constant. Values of 16.2 eV for the deformation potential constant, 1.7 × 104d1/2/cm for the piezoelectric constant, and 280°K for the optical phonon temperature give good agreement between experiment and theory when screening is neglected. The effects of electron degeneracy and screening upon energy relaxation are discussed.
ISSN:0003-6951
DOI:10.1063/1.1653004
出版商:AIP
年代:1969
数据来源: AIP
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8. |
OBSERVATION OF RAMAN SCATTERING BY WATER VAPOR IN THE ATMOSPHERE |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 295-297
S. H. Melfi,
J. D. Lawrence,
M. P. McCormick,
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摘要:
Raman backscatter of a frequency‐doubled ruby laser beam by water vapor has been observed in the atmosphere, using an optical radar system. This return along with a Raman nitrogen return, has been used to calculate a relative water‐vapor mixing ratio profile in the atmosphere to an altitude of approximately 2 km.
ISSN:0003-6951
DOI:10.1063/1.1653005
出版商:AIP
年代:1969
数据来源: AIP
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9. |
A NEW TYPE OF SURFACE SPIN WAVE IN FERROMAGNETIC FILMS |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 297-299
R. E. De Wames,
T. Wolfram,
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摘要:
A new type of surface spin wave occurs in a ferromagnetic film with an applied magnetic fieldperpendicularto the surface when the dipole and exchange energies are comparable. The surface wave propagates parallel to the surface but has a wave vector whose normal component iscomplex. States having a high degree of localization of the spin wave amplitude near the surfaces can occur.
ISSN:0003-6951
DOI:10.1063/1.1653006
出版商:AIP
年代:1969
数据来源: AIP
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10. |
INTERACTION BETWEEN ELASTIC SURFACE WAVES IN PIEZOELECTRIC MATERIALS |
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Applied Physics Letters,
Volume 15,
Issue 9,
1969,
Page 300-302
L. O. Svaasand,
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摘要:
Nonlinear interaction between elastic surface waves and an almost uniform time‐dependent electric field is demonstrated in LiNbO3at 17 MHz.
ISSN:0003-6951
DOI:10.1063/1.1653007
出版商:AIP
年代:1969
数据来源: AIP
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