High-efficiency optical analog computers of incoherent light on semiconductor nanostructures

2008 ◽  
Author(s):  
P. G. Kasherininov ◽  
A. A. Tomasov
Keyword(s):  
High Efficiency ◽  
Semiconductor Nanostructures ◽  
Incoherent Light ◽  
Optical Analog

Hollow anisotropic semiconductor nanoprisms with highly crystalline frameworks for high-efficiency photoelectrochemical water splitting

2019 ◽  
Vol 7 (14) ◽  
pp. 8061-8072 ◽  
Author(s):  
Erhuan Zhang ◽  
Jia Liu ◽  
Muwei Ji ◽  
Hongzhi Wang ◽  
Xiaodong Wan ◽  
...  
Keyword(s):  
Water Splitting ◽  
Special Interest ◽  
High Efficiency ◽  
Semiconductor Nanostructures ◽  
Photoelectrochemical Water Splitting ◽  
Anisotropic Semiconductor ◽  
Structure Morphology ◽  
Tunable Structure ◽  
Pec Water Splitting

Construction of hollow anisotropic semiconductor nanostructures that possess excellent crystallinity, flexibly tunable structure/morphology and aqueous dispersity is of special interest for photoelectrochemical (PEC) water splitting

Electrical and Optical Properties of Polysilicon Sheets for Photovoltaic Devices Grown From Powder

1990 ◽  
Vol 182 ◽  
Author(s):  
Natko B. Urli
Keyword(s):  
Electrical Transport ◽  
High Efficiency ◽  
Low Cost ◽  
Spectral Response ◽  
Short Circuit ◽  
Zone Melting ◽  
Back Surface ◽  
Incoherent Light ◽  
Novel Technologies ◽  
Pure Graphite

AbstractIn a search for low-cost and high efficiency solar cell manufacturing, several techniques of growing thin silicon sheets from powder have been adopted, such as: plasma spraying on various substrates, zone-melting using incoherent focussed light as heat source, and low-angle horizontal pulling of thin ribbon over the melted tin-lead support. Undoped, and n- and p-type silicon powders of various grain sizes have been used as starting materials, with pure graphite, quartz, or low-cost ceramics serving as temporary or permanent substrates. N+/p +/n junctions, and back surface fields were formed by implanting PF 5 and BF 3+ ions in a glow discharge ion implanter at ultralow energies (less than 1 keg) and high total ion doses. Ion induced damage was annealed by RTP in the incoherent light furnace at temperatures as low as 700°C.Structural and optoelectronic properties of as-grown and processed thin polysilicon sheets were determined by Raman spectroscopy, spectral response, and electrical transport measurements. A sharp peak at 520 cm−1 in the Raman spectra, associated with TO ((Г) phonons, indicated a good crystallinity of polysilicon sheets. High values of short-circuit currents, and an almost flat spectral response down to 400 nm, without intentionally applying a surface passivating oxide, illustrate the advantage of the applied novel technologies.

scholarly journals Optical Realization of Wave-Based Analog Computing with Metamaterials

2020 ◽  
Vol 11 (1) ◽  
pp. 141
Author(s):  
Kaiyang Cheng ◽  
Yuancheng Fan ◽  
Weixuan Zhang ◽  
Yubin Gong ◽  
Shen Fei ◽  
...  
Keyword(s):  
High Speed ◽  
High Efficiency ◽  
Quantum Algorithms ◽  
Optical Computing ◽  
Research Field ◽  
Analog Computing ◽  
Light Waves ◽  
Recent Developments ◽  
Optical Analog ◽  
Easy Integration

Recently, the study of analog optical computing raised renewed interest due to its natural advantages of parallel, high speed and low energy consumption over conventional digital counterpart, particularly in applications of big data and high-throughput image processing. The emergence of metamaterials or metasurfaces in the last decades offered unprecedented opportunities to arbitrarily manipulate the light waves within subwavelength scale. Metamaterials and metasurfaces with freely controlled optical properties have accelerated the progress of wave-based analog computing and are emerging as a practical, easy-integration platform for optical analog computing. In this review, the recent progress of metamaterial-based spatial analog optical computing is briefly reviewed. We first survey the implementation of classical mathematical operations followed by two fundamental approaches (metasurface approach and Green’s function approach). Then, we discuss recent developments based on different physical mechanisms and the classical optical simulating of quantum algorithms are investigated, which may lead to a new way for high-efficiency signal processing by exploiting quantum behaviors. The challenges and future opportunities in the booming research field are discussed.

scholarly journals High-efficiency photovoltaics based on semiconductor nanostructures

2011 ◽  
Author(s):  
Paul K.L. Yu ◽  
◽  
Edward T. Yu ◽  
Deli Wang
Keyword(s):  
High Efficiency ◽  
Semiconductor Nanostructures

Characterization of Ion-Implanted Si Rapidly Annealed with Incoherent Light

1981 ◽  
Vol 4 ◽  
Author(s):  
J. L. Benton ◽  
G. K. Celler ◽  
D. C. Jacobson ◽  
L. C. Kimerling ◽  
D. J. Lischner ◽  
...  
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Complete Recovery ◽  
Depletion Region ◽  
Device Fabrication ◽  
Incoherent Light ◽  
Carrier Lifetimes ◽  
Transient Spectroscopy ◽  
Capacitance Transient

ABSTRACTIrradiation of Si wafers for 5 to 10 sec with high intensity tungsten halogen lamps produces complete recovery of the displacement damage resulting from ion implantation. Data for two different thermal cycles are presented, with As and B implant doses ranging from 1013 to 1016 ions cm−2. Sheet resistance measurements combined with Rutherford backscattering indicate full electrical activation of dopants with very little diffusion. Carrier lifetimes measured by a photoconductive method and by diode reverse recovery compare favorably with furnace annealing data, and capacitance transient spectroscopy reveals a low density of defects in the junction depletion region. These results combined with the inherent advantages of low cost and high efficiency make Rapid Thermal Annealing ideally suited for VLSI device fabrication.

Microcalorimeters for X-Ray Spectroscopy

1988 ◽  
Vol 102 ◽  
pp. 41
Author(s):  
E. Silver ◽  
C. Hailey ◽  
S. Labov ◽  
N. Madden ◽  
D. Landis ◽  
...  
Keyword(s):  
High Resolution ◽  
High Efficiency ◽  
Thermal Response ◽  
Low Noise ◽  
High Resolution Spectroscopy ◽  
Superconducting Transition ◽  
Sapphire Substrates ◽  
Laboratory Plasmas ◽  
Adiabatic Demagnetization ◽  
Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

Imaging and diffraction modes in Scanning Transmission Electron Microscopy

1986 ◽  
Vol 44 ◽  
pp. 684-687
Author(s):  
J. M. Cowley ◽  
R. Glaisher ◽  
J. A. Lin ◽  
H.-J. Ou
Keyword(s):  
Scanning Transmission Electron Microscopy ◽  
High Efficiency ◽  
Fiber Optic ◽  
Image Intensifier ◽  
Detector System ◽  
Detector Plane ◽  
Secondary Electrons ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Special Detector

Some of the most important applications of STEM depend on the variety of imaging and diffraction made possible by the versatility of the detector system and the serial nature, of the image acquisition. A special detector system, previously described, has been added to our STEM instrument to allow us to take full advantage of this versatility. In this, the diffraction pattern in the detector plane may be formed on either of two phosphor screens, one with P47 (very fast) phosphor and the other with P20 (high efficiency) phosphor. The light from the phosphor is conveyed through a fiber-optic rod to an image intensifier and TV system and may be photographed, recorded on videotape, or stored digitally on a frame store. The P47 screen has a hole through it to allow electrons to enter a Gatan EELS spectrometer. Recently a modified SEM detector has been added so that high resolution (10Å) imaging with secondary electrons may be used in conjunction with other modes.

Low-energy point-reflection EM

1995 ◽  
Vol 53 ◽  
pp. 610-611
Author(s):  
J. C. H. Spence ◽  
X. Zhang ◽  
J. M. Zuo ◽  
U. Weierstall ◽  
E. Munro ◽  
...  
Keyword(s):  
Low Voltage ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Experimental Point ◽  
Crystalline Substrate ◽  
Point Reflection ◽  
Reflection Geometry ◽  
Optical Analog ◽  
Point Projection ◽  
Atomically Flat

The limited penetration of the low-voltage point-projection microscope (PPM) may be avoided by using the reflection geometry to image clean surfaces in ultra-high vacuum. Figure 1 shows the geometry we are using for experimental point-reflection (PRM) imaging. A nanotip field-emitter at about 100 - 1000 volts is placed above a grounded atomically flat crystalline substrate, which acts as a mirror and anode. Since most of the potential is dropped very close to the tip, trajectories are reasonably straight if the sample is in the far-field of the tip. A resolution of 10 nm is sought initially. The specular divergent RHEED beam then defines a virtual source S' below the surface, resulting in an equivalent arrangement to PPM (or defocused CBED). Shadow images of surface asperities are then expected on the distant detector, out of focus by the tip-to-sample distance. These images can be interpreted as in-line electron holograms and so reconstructed (see X. Zhang et al, these proceedings). Optical analog experiments confirm the absence of foreshortening when the detector is parallel to the surface.

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