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Enhanced Photocurrent of All-Inorganic Two-Dimensional Perovskite Cs[subscript 2]PbI[subscript 2]Cl[
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Substrate controls photovoltage, photocurrent and carrier separation in nanostructured Bi 2 S 3 films
Bi 2 S 3 is a narrow bandgap semiconductor of interest for the construction of solar energy devices and can be synthesized by E-Chem/Sulfurization approach. The (photo)current from Bi 2 S 3 can be controlled by the substrate workfunction and its resistance.
Shift photovoltaic current and magnetically induced bulk photocurrent in piezoelectric sillenite crystals
Recently, it has been shown how shift and ballistic currents in piezoelectric sillenite crystals Bi 12 GeO 20 and Bi 12 SiO 20 can be separated experimentally under the assumption that the shift component of the circular current is small. However, it has been claimed that the shift and ballistic currents cannot be quantified by this method, due to the magnetophotovoltaic effect caused either by the change of the crystal's spatial symmetry in the magnetic field or by the breaking of time-reversal symmetry. Presently, we report observations of photovoltaic currents in Bi 12 SiO 20 , excited by linearly and circularly polarized light under weak external magnetic field, as well as measurements of the corresponding photo-Hall signals. Further, we demonstrate that the magnetophotovoltaic current constitutes a significant fraction of the measured current in the Hall direction for Bi 12 SiO 20 under specific experimental conditions.
Spatially dispersive helicity-dependent photocurrent in Dirac semimetal Cd 3 As 2 nanobelts
Not provided.
Transverse chiral magnetic photocurrent induced by linearly polarized light in mirror-symmetric Weyl semimetals
Not Available
Self-Aligned, Selective Area Poly-Si/SiO2 Passivated Contacts for Enhanced Photocurrent in Front/Back Solar Cells
Poly-Si/SiO 2 passivated contact front/back solar cells suffer low Jsc due to parasitic absorption in the front poly-Si layer. We demonstrate a self-aligned, selective area front contact dry-etch technique that retains the as-deposited poly-Si beneath the metal grid lines but thins it elsewhere. Jsc improves by 0.7 mA/cm 2 over our standard 40 nm thick poly-Si. Greater improvements are expected with thicker poly-Si needed for fired metal contacts. Surface passivation is slightly diminished with poly-Si thinning but can be partially restored with rehydrogenation.
Gamma-Ray- and Neutron-Induced Photocurrent and Readout Noise in LYSO+SiPM Packages
Not provided.
A Numerical Compact Photocurrent Model and its Implementation via Xyce-PyMi.
Abstract not provided.
A Compact Delayed Photocurrent Model Based on a Reduced Order Data-Driven Exponential Time Integrator.
Abstract not provided.
Transient Photocurrent from High-Voltage Vertical GaN Diodes Irradiated with Electrons:Experiments and Simulations.
Abstract not provided.
Data-driven compact photocurrent models
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Gray box photocurrent models: a data-driven approach for compact radiation modeling
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Calculation of transient photocurrents in insulators with trapped space charge.
The transit times and pulse shapes of photoinjected carriers moving in the presence of trapped space charge are derived. Two distributions are considered: uniformly trapped space charge, and trapped space charge decreasing exponentially in position from the injecting electrode. The pulse shapes are in some cases similar to those arising from transient space-charge-limited currents. The results in the case of the exponentially trapped space charge may have application in analysis of pulses taken in the presence of space charge trapped in the excitation layer or on the surface of insulators.
Correlation of photocurrent-voltage curves with flat-band potential for stable photoelectrodes for the photoelectrolysis of water
Using the differential capacitance technique, the flat-band potential of n-type TiO2, SnO2, SrTiO3, KTaO3, and KTa(0.77)Nb(0.23)O3 electrodes has been determined as a function of pH in aqueous electrolytes. Plots of flat-band potential vs. pH are linear in all cases and have a slope of approximately 0.059 V/pH unit. The flat-band potential correlates nicely with the onset for photoanodic currents corresponding to O2 evolution at the n-type semiconductor and H2 at the dark Pt cathode. The ordering of flat-band potentials at a given pH is SrTiO3 of the order of KTaO3 of the order of KTa(0.77)Nb(0.23)O3 greater than TiO2 greater than SnO2 (SnO2 most positive vs a saturated calomel electrode).
A note on photocurrents in extrinsic semiconductors
The advent of the concept of holes and careful determination of mobilities have made it possible to realize that the potential difference between the contacts of an irradiated semiconductor in the absence of current flow is due to the difference in mobility of electrons and holes. In this paper, a preliminary analysis shows that charge neutrality and zero-current condition are compatible. This situation is clarified and it is found that the equation for the electric field E in the absence of current is not absolutely correct even under low-level injection conditions. In particular, it is shown that fairly large currents can be generated by suitable light sources, currents which are entirely due to the disparity between electron and hole mobilities.
The decrease in effective photocurrents due to saddle points in electrostatic potentials near differentially charged spacecraft
The reported investigation had the objective to illustrate the presence of important multidimensional effects in spacecraft charging. Two-dimensional codes have been under development by Parker (1976). A description is presented of a calculation which was performed using the three-dimensional NASA Charging Analyzer Program (NASCAP). NASCAP was run to calculate the electrostatic potentials on the surface of, and in the space surrounding, a sunlit Teflon-coated sphere. Currents to the sunlit surfaces were determined on the basis of an approximate photosheath model for strong differential charging.