UScholar Works
 
Filters: School Or College: "College of Science" Collection: "ir_uspace"
1 - 25 of 77
Number of results to display per page
CreatorTitleDescriptionSubjectDate
1 Wu, Yong-ShiPerturbative formulation and nonadiabatic corrections in adiabatic quantum-computing schemesAdiabatic limit is the presumption of the adiabatic geometric quantum computation and of the adiabatic quantum algorithm. But in reality, the variation speed of the Hamiltonian is finite. Here we develop a general formulation of adiabatic quantum computing, which accurately describes the evolution...Perturbative formulation; Nonadiabatic corrections; Adiabatic2004-02
2 Williams, Clayton C.Mapping of mobile charges on insulator surfaces with the electrostatic force microscopeMigration of surface ions in lateral fields on insulator surfaces may modify the electrical characteristics of underlying semiconductor structures causing device instabilities. A high sensitivity electrostatic force microscope is used to image the movement and spatial distribution of surface ions on...Insulator surfaces; Surface ions; Electrostatic force microscope1993
3 Williams, Clayton C.Two step dopant diffusion study performed in two dimensions by scanning capacitance microscopy and TSUPREM IVWe report the results of a two-step two- dimensional (2D) diffusion study by scanning capacitance microscopy (SCM) and 2D SUPREM IV process simulation. A quantitative 2D dopant profile of a gate-like structure is measured with the SCM on a cross-sectioned polished silicon wafer. The gate-like struct...Scanning capacitance microscopy; SCM; Doping1998
4 Boehme, ChristophSpin-dependent recombination - an electronic readout mechanism for solid state quantum computersIt is shown that coherent spin motion of electron-hole pairs localized in band gap states of silicon can influence charge carrier recombination. Based on this effect, a readout concept for silicon based solid-state spin-quantum computers as proposed by Kane is suggested. The 31P quantum bit (qbit) i...Spin readout; qbit; Spin-dependent recombination2002-10
5 Ailion, David CharlesLow cost high linearity solid state digital double boxcarIn this article, we describe a digital solid state double boxcar of infinite holding time and very high linearity. It uses a Hewlett-Packard (HP2212 A-M3) voltage-to-frequency converter (VFC) whose output is accumulated on a running counter, thereby providing signal averaging with an infinite holdin...High linearity; Boxcar; Instruments, Physics1969
6 Dawson, KyleHigh-voltage-compatible fully depleted CCDsWe describe charge-coupled device (CCD) development activities at the Lawrence Berkeley National Laboratory (LBNL). Back-illuminated CCDs fabricated on 200-300 fxm thick, fully depleted, high-resistivity silicon substrates are produced in partnership with a commercial CCD foundry. The CCDs are full...Large Synoptic Survey Telescope; X-ray emission; XMM22352006
7 Williams, Clayton C.Depth dependent carrier density profile by scanning capacitance microscopyThe depth dependent carrier density was measured on an arsenic implanted silicon sample using scanning capacitance microscopy (SCM). The capacitance versus voltage scan was performed by applying dc biases with a dither ac signal. A strong dc bias dependence was observed at the interface of an abru...Carrier density; Silicon submicrometer technology; Scanning capacitance microscopy1997
8 Williams, Clayton C.Depth dependent carrier density profile by scanning capacitance microscopyThe depth dependent carrier density was measured on an arsenic implanted silicon sample using scanning capacitance microscopy (SCM). The capacitance versus voltage scan was performed by applying dc biases with a dither ac signal. A strong dc bias dependence was observed at the interface of an abru...Carrier density; Silicon submicrometer technology; Scanning capacitance microscopy1997
9 Saam, BrianProtection circuitry for high-power diode laser arraysA comprehensive protection scheme is presented for use with high-power (;500 W dc input! diode laser arrays. The circuitry requires no separate power, using instead the voltage from the laser's power supply. Overcurrent and overvoltage silicon controlled rectifier crowbars are the primary protection...Protection circuitry; High-power diode laser arrays1998
10 Lupton, John MarkTime-gated electroluminescence spectroscopy of polymer light-emitting diodes as a probe of carrier dynamics and trappingWe present time-gated electroluminescence (EL) spectroscopy of a polyfluorene-based conjugated polymer. The technique is shown to be sensitive enough to pick out impurity emission orders of magnitude weaker than the cw emission. By considering the temperature dependence of the delayed emission spect...Time-gated electroluminescence spectroscopy; Carrier dynamics; Trapping; Delayed emission2002-04
11 Boehme, ChristophElectrical detection of coherent 31P spin quantum statesIn recent years, a variety of solid-state qubits has been realized, including quantum dots [1, 2], superconducting tunnel junctions [3, 4] and point defects [5, 6]. Due to its potential compatibility with existing microelectronics, the proposal by Kane [7, 8] based on phosphorus donors in Si has als...Spin quantum states; Qubits; Rabi flops2006-11-19
12 Hughes, Kelly T.ATPase-Independent Type-III Protein Secretion in Salmonella entericaType-III protein secretion systems are utilized by gram-negative pathogens to secrete building blocks of the bacterial flagellum, virulence effectors from the cytoplasm into host cells, and structural subunits of the needle complex. The flagellar type-III secretion apparatus utilizes both the energy...2014-01-01
13 Ailion, David CharlesLow cost integrated circuit versatile pulse and frequency counterIn this paper we describe a compact multipurpose counter whose design is based on the use of plastic integrated circuits. The circuit contains about $90 worth of semiconductor components and is very easy to wire; nevertheless, it is extremely versatile. It consists of dual 107 and 106 counters which...Integrated circuits; Counters; Physics instruments1969
14 Dawson, KyleCCD testing and characterization for dark energy surveyA description of the plans and infrastructure developed for CCD testing and characterization for the DES focal plane detectors is presented. Examples of the results obtained are shown and discussed in the context of the device requirements for the survey instrument.DES2006
15 Lupton, John MarkEvidence for temperature-independent triplet diffusion in a ladder-type conjugated polymerWe study the temperature dependence of triplet formation and decay by considering the phosphorescence dynamics in a prototypical conjugated polymer matrix. The dynamics of triplet formation as a function of temperature are unraveled by applying an electric field during optical singlet generation a...Triplet diffusion; Triplet excitons; Ladder-type conjugated polymers; Temperature dependence2006-12
16 Dawson, KyleTechnology development for 4k x 4k, back-illuminated, fully depleted scientific CCD imagersWe have developed scientific charge-coupled devices (CCDs) that are fabricated on high-resistivity, n-type silicon substrates, and have demonstrated fully depleted operation for substrate thicknesses of 200-675 μm with formats as large as 2048 × 4096 (15 μm pixels) and 3512 × 3512 (10.5 μm pix...Gettering2007-10
17 Williams, Clayton C.Advances in experimental technique for quantitative two dimensional dopant profiling by scanning capacitance microscopySeveral advances have been made toward the achievement of quantitative two-dimensional dopant and carrier profiling. To improve the dielectric and charge properties of the oxide-silicon interface, a method of low temperature heat treatment has been developed which produces an insulating layer with c...Doping; Scanning capacitance microscope; SCM1999
18 Williams, Clayton C.Direct imaging of SiO2 thickness variation on Si using modified atomic force microscopeFabrication techniques of metal-oxide-semiconductor ~(MOS) transistors have been improved very rapidly during the last several decades. With this trend, scaling down of MOS transistors is necessary to improve the speed of circuits and the packing density of discrete devices. Both lateral and vertic...Silicon dioxide; Oxide layer; Phosphorus ions; Oxide capacitance; Dopant profile1996-03-01
19 Lupton, John MarkStimulated emission depletion of triplet excitons in a phosphorescent organic laserTriplet formation is investigated in an optically pumped polymer laser by detecting the phosphorescence emission after excitation. A clear correlation is observed between the onset of lasing and a saturation of phosphorescence intensity due to stimulated emission depletion of the singlet state and t...Triplet excitons; Triplet formation; Emission depletion; Phosphorescent organic laser; Optically pumped polymer laser2006
20 Mattis, Daniel C.Soluble Ising model in 2+1/N dimensions and XY model in 1+1/N dimensionsThe XY model is exactly soluble on a comblike structure, by means of a modified Jordan-Wigner transformation. This method is used to reduce the transfer matrix of the Ising model, on planes which are joined to each other at one edge, to a soluble canonical form.Jordan-Wigner transformation1979-07
21 Kieda, David B.Antarctic impulsive transient antenna (ANITA) instrumentationWe will report on the details of the ANITA instrument. This instrument is fundamentally a broadband antenna, which is arrayed and constructed in such a way as to be optimized for the detection and characterization of high-energy neutrino cascades [1]. The requirement to maximize the detector view of...ANITA; Antarctic Impulsive Transient Antenna; Neutrino; Balloon; Antarctica2003
22 Lupton, John MarkIntrinsic room-temperature electrophosphorescence from a π-conjugated polymerElectrically induced phosphorescence from a poly(para-phenylene) ladder-type polymer is observed for the first time and characterized using time resolved spectroscopy. Short-lived phosphorescence is also observed in gated fluorescence spectra and is found to be quenched reversibly by oxygen. Therm...pi-conjugated polymers; Electrophosphorescence; Ladder-type polymer; Gated fluorescence spectra2002-09
23 Mishchenko, EugeneZero-bias anomaly in two-dimensional electron layers and multiwall nanotubesThe zero-bias anomaly in the dependence of the tunneling density of states n (e) on the energy e of the tunneling particle for two- and one-dimensional multilayered structures is studied. We show that for a ballistic two-dimensional (2D) system the first-order interaction correction to density of s...Spin-orbit coupling; Coulomb interaction2002-05
24 Symko, Orest GeorgeNoise characteristics and instabilities of long Josephson junctionsIn a magnetic field, current biased long Josephson junctions exhibit the dynamics of fluxon motion which are affected by fluctuations. These consist of telegraph noise at voltage steps and instabilities due to chaotic behavior. Results on long junctions with McCumber number fic ranging from 10 to 10...Fluxon motion; Current biased; Instabilities; Telegraph noise; Perturbed sine-Gordon equation1989-03
25 Mishchenko, EugenePolarized electric current in semiclassical transport with spin-orbit interactionSemiclassical solutions of two-dimensional Schrödinger equation with spin-orbit interaction and smooth potential are considered. In the leading order, spin polarization is in-plane and follows the evolution of the electron momentum for a given subband. Out-of-plane spin polarization appears as a ...Spin-polarized current; Sharvin conductance; Spin-orbit coupling2006-10
1 - 25 of 77