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An optoelectronic switch with both n- and p-type delta-doped (-doped) quantum wells was investigated. The -doped structures formed potential wells for the carrier accumulation and potential barriers for the carrier injection. Being possessed of -doped sheets with different doping levels, the potential barriers were sequentially collapsed to produce a double negative-differential-resistance (NDR) phenomenon in the current–voltage (I–V) characteristics of the device, due to the carrier accumulation in the potential wells. The device also showed an optical function related to the barrier heights controllable by incident light. 相似文献
64.
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采用高速转镜分幅相机和电探针技术研究了猛炸药RHT-901和钝感炸药IHE-2的爆轰波直角绕射图像和不同位置上的爆轰波传播时间。从研究得出,两种炸药都在拐角顶点附近绕射,爆轰波传播时间增长,爆速变小。但是两种炸药绕射爆轰波的状态不一样,钝感炸药IHE-2中爆轰波绕过直角时,在拐角顶点附近约10 mm范围内炸药未完全反应,猛炸药RHT-901中爆轰波绕过直角时未出现类似现象。两者相比,钝感炸药中绕射爆轰波速度变化大,波阵面曲率半径小,而猛炸药的绕射爆轰波速度变化小,波阵面曲率半径大。这说明炸药的爆轰波绕射与炸药的冲击感度、反应区宽度有关。 相似文献
69.
A self-consistent problem of interaction of two dipole atoms separated by an unrestricted distance with the field of a quasi-resonance
light wave was solved on the assumption that the investigated atoms are Lorentz linear oscillators and the polarizing fields
inside the system consist of the Coulomb and the retarded parts. The solution obtained was investigated for the case where
the atoms have the same polarizability and the distance between them is much smaller than the length of the external light
wave. Formulas for the electric fields inside a small object and outside it have been obtained. It is shown that inside a
small two-atom object there can take place longitudinal and transverse optical vibrations accompanied by corresponding dispersion
effects depending on the interatomic distance and the angle between the axis of the system and the direction of propagation
of the external light wave. The field outside the small object in the wave zone is linearly polarized when the external wave
has linear polarization. However, the direction of polarization of the corresponding waves is largely determined by their
frequency. It is also shown that the amplitude of the field outside the small object in the wave zone depends greatly on the
frequency of the external field and the interatomic distance. The effects observed are considered as a near-field effect in
optics of small objects. This phenomena makes it possible to investigate the structure of small objects with the use of optical
radiation.
Ul'yanovsk Branch of the Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 48 Goncharov Str., Ul'yanovsk,
432700, Russia; e-mail: gadomsky@quant.univ.simbirsk.su. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6,
pp. 765–770, November–December, 1999. 相似文献
70.
V. V. Sobolev 《Journal of Applied Spectroscopy》1999,66(3):319-335
The article surveys the main unsolved problems of the electronic structure of nonmetals in a wide energy region of fundamental
absorption.
Udmurtia State University, 71, Krasnogeroiskaya Str., Izhevsk, 426034, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 66, No. 3, pp. 299–315, May–June, 1999. 相似文献