<title>Photodetectors for fast images recognition on structures with Shottky barriers</title>

Abstract

The paper proposes semiconducting photodetectors for fast images recognition. Photodetector is illuminated simultaneously with two beams of " intrinsic" light. One of the beams carries image of the reference object the other provides image of the current object. While the images are identical the photoresponse turns to be maximum. Photodetector represents itself a processor which multiplies the the corresponding elements of these images and integrates the result over the square. Photodetector is a plane-parallel plate of crystal with high resistance (GaAs, CdTe) with a photosensitive n -p junction at one side and Shottky barrier (optical detecting medium) at the other one.

Electrically pumped random lasing based on an Au–ZnO nanowire Schottky junction

“…Under a sufficiently high forward bias, the sharply bent energy band region appears and holes can directly tunnel to the valence band of ZnO from the positive pole. 27 These holes readily interact with electrons in the conduction band to form excitons and emit light through excitonic EL. 28 Due to the limited hole injection, the exciton recombination process is believed to be responsible for the lasing behavior since population inversion is not necessary in excitonic lasing generation.…”

Electrically Pumped Whispering Gallery Mode Lasing from Au/ZnO Microwire Schottky Junction

“…Since the electrons and holes are flowing in the opposite direction, there are ample probabilities for them to couple with each other and form excitons. [27,28] These excitons then recombine to emit light almost instantaneously. [28] It should be noted that this device is different with the metal-insulator-semiconductor laser device, where a large barrier at the metal-semiconductor interface is used to confine electrons in the semiconductor for lasing as reported in Ref.…”

Ultraviolet random lasing from asymmetrically contacted MgZnO metal-semiconductor-metal device

“…Hence, holes can tunnel directly and also through traps to the valence band of Mg 0.12 Zn 0.88 O:N film from the Ni contact across the sharply bent energy band region. 36,37 Moreover, some holes are created through the generation process due to the presence of high electric field near the Ni-contact region. These injected holes readily form excitons and contribute to the excitonic electroluminescence.…”