摘要:

High‐field‐induced breakdown associated with light emission in anthracene crystals has been observed. The color of the emitted light is light blue in the 4000–4500‐Å spectral region. The breakdown is identified as avalanche breakdown. The emitted light is due to radiative electron‐hole recombinations.

ISSN:0003-6951    

DOI:10.1063/1.1653961

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Nonlinear optical measurements show 5‐nitrouracil (5NU) to be phase matchable with a co‐efficient approximately equal to that of lithium iodate [d36(5NU) = (1.0 ± 0.2)d33(LiIO3)]. The large optical nonlinearity is attributed to a highly acentric molecular distribution of non‐&sgr;‐bonded electrons. Air‐stable nonoptically damageable single crystals were grown from an aqueous solution. X‐ray results show the material to crystallize in the orthorhombic space groupP212121containing four molecules per unit cell of dimensionsa0= 9.94 ± 0.03 Å,b0= 10.30 ± 0.03 Å, andc0= 5.47 ± 0.02 Å. The crystals are transparent from 1.5 to 0.5 &mgr;.

ISSN:0003-6951    

DOI:10.1063/1.1653962

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The structure of a proposed several‐megaamperes discharge created along a narrow filament of laser‐produced ionization through a high‐density deuterium‐tritium gas mixture is discussed. This initiation technique provides a convenient method for creating long straight gas‐embeddedzpinches (or screw pinches if aBzis included) which may be of thermo‐nuclear interest.

ISSN:0003-6951    

DOI:10.1063/1.1653963

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Detailed observation of the photoconductive gain saturation in high‐resistivity Si:B samples is reported. The calculated saturated gain of 0.52 agrees well with the theoretical prediction ofGsat= ½. These measurements strongly suggest that this phenomenon is a general characteristic of all high‐impedance extrinsic photoconductors.

ISSN:0003-6951    

DOI:10.1063/1.1653964

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

A subtractive‐microwave‐holographic technique is described in this letter. This technique appears to be novel in that it displays only the difference of the two dissimilar microwave fields. The effect is achieved by making use of the phase reversal which occurs when a contact print is made of the microwave hologram. The technique was demonstrated by subtracting the microwave image of a coin from that of three coins. To show the practicability of the technique, it was applied to the diagnosis of a plasma discharge. The fact that this method can eliminate the masking effects scattered by the glass envelope and its supports is a substantial improvement over other microwave diagnostic tools.

ISSN:0003-6951    

DOI:10.1063/1.1653965

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Profiles of channeled31P ions over the energy range 30–600 keV have been measured in ⟨100⟩, ⟨111⟩, and ⟨110⟩ Si. The maximum rangeRmaxof the channeled ions is nearly the same for the ⟨100⟩ and ⟨111⟩ directions and is significantly greater for the ⟨110⟩ direction.

ISSN:0003-6951    

DOI:10.1063/1.1653967

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

A new type of voltage‐controlled differential‐negative‐resistance effect was observed in ann‐type surface inversion layer of a silicon MOS field‐effect transistor with a very high mobility of 104cm2/V sec at low temperatures.

ISSN:0003-6951    

DOI:10.1063/1.1653968

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

An infrared parametric oscillator using proustite and pumped at 1.065 &mgr;m 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 &mgr;m 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 &mgr;m now appear feasible.

ISSN:0003-6951    

DOI:10.1063/1.1653969

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Properly designed GaAs&sngbnd;AlxGa1−xAs double heterostructures produce strong optical waveguides. The propagation constants of the waveguide modes can be readily modulated by the linear electro‐optic effect. Measurements at a wavelength &lgr; = 1.153 &mgr;m have yielded a phase modulation of 180° with ‐10 V applied bias to a device only 1 mm long. The power necessary to phase modulate light at &lgr; ≈ 1 &mgr;m by 1 rad is of the order of 0.1 mW per 1‐MHz band‐width. The power dissipation is very strongly dependent on wavelength. At present, the high‐frequency modulation is limited by the series resistance and capacitance of the device. The highest cutoff frequency determined thus far, ≈ 4 GHz, is considerably lower than that calculated based on the geometry and material properties.

ISSN:0003-6951    

DOI:10.1063/1.1653970

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

A light‐guiding thin polyurethane film, doped with rhodamine 6G, is coated on the surface of a cylindrical glass rod and pumped with a pulsed Ne laser. A prism‐film coupler produces two output beams corresponding to clockwise and counterclockwise oscillations around the circumference of the rod. Unidirectional operation is obtained when one of the output beams is reflected back into itself. A maximum directionality ratio of 17 was measured.

ISSN:0003-6951    

DOI:10.1063/1.1653971

出版商:AIP    

年代:1972

数据来源: AIP