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Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable and the source should be electrically driven. Several design strategies addressing these requirements have been proposed. In the cavity-based...
Quasi-static microring models assume the intracavity optical field adiabatically follows the modulated parameter(s). A non-quasi-static model shows the modulation of the microring coupling coefficient breaks the traditional tradeoffs between the modulation rate and resonator linewidth.
We investigate the dynamics of optoelectronic oscillators (OEOs) employing high-speed resonant tunneling diodes (RTDs) integrated with a laser diode. This RTD-OEO excitable system is analyzed in the context of two applications: ultra high spectral purity microwave generation for sensing and telecommunication networks and high-speed excitable pulse generation for biologically inspired information processing.
We experimentally characterize the innovative cloak, which enables arbitrary multi-objects hidden with movements and visions by the dielectric metamaterials. The field distribution of the cloak is demonstrated through the FITD simulation method and then is mapped through the microwave probe attached to the vector network analyzer. The two results are consistent with each other.
The light-matter interaction in planar nanostructures with applications in photovoltaic devices is investigated by means of a microscopic quantum-kinetic theory based on the non-equilibrium Green's function formalism. The Dyson and Keldysh equations for the Green's functions of photons are solved numerically. The result is used to couple the optical and electronic degrees of freedom via respective...
In rigorous optical modeling and simulation of thin-film solar cells a few constraints and bottlenecks have been addressed recently. Two of them are related to how to include thick incoherent layers in the coherent finite element based simulations and how to describe and include non-conformal growth of layers in a thin-film solar cell. In this paper we present and apply three different solutions to...
Based on the transfer-matrix method and the complex wave impedance approach, this unified electrical and optical numerical simulation thoroughly analyzes the impacts of the design parameters on the transport mechanisms and device characteristics of radial p-n junction GaAs/AlxGa1−xAs core-shell nanowire solar cells. By optimizing the doping density of the core and shell, core radius, shell thickness,...
Patterned silicon solar cells are fully modeled optically and electrically using Lumerical Solutions' optical simulation software, FDTD Solutions and electrical simulation solver, DEVICE. The optical simulation calculates the spatial distribution of photon absorption in the silicon when the cell is illuminated by unpolarized sunlight with the AM1.5 solar spectral intensity. The photon absorption data...
Optomechanical nanocavities allow nanomechanical resonances to be measured optically with high sensitivity. We have created a new type of photonic crystal nanocavity optomechanical sensor optimized for detecting sources of torque and other forces which can deflect nanoscale cantilevers. This nanocavity consists of two precisely engineered photonic Bragg mirrors patterned in silicon cantilevers and...
The dependence of laser beam induced current (LBIC) on the junction structure of n+-on-p HgCdTe photodiode has been numerically investigated. The simulated LBIC profiles are in good agreement with the experimental data. It is found that the peak LBIC magnitude is close to a linear relationship with both junction depth and length. In addition, the shape between two peaks becomes more flat with the...
Excessive depth of optically active quantum wells (QWs) in III-nitride light emitters of visible range is one of the main causes of inhomogeneous carrier injection in multiple-quantum-well (MQW) device active region. Deeper QWs imply stronger inhomogeneity of carrier distribution across the active region and support large residual charges of marginally located N-side and P-side QWs. Drift-diffusion...
Charge sensitive infrared phototransistors (CSIP) are well known for their capability for response spectrum tuning and single photon detection. In this paper, we established a physical model for a charge sensitive infrared phototransistor operating at 45μm wavelength using the Crosslight Apsys software. Several key physical mechanisms involved such as inter-subband optical transition and resonant...
This paper presents a study on asymmetric slot waveguide resonators to be used as sensing elements in Laboratory on a chip (LOC). They combine slot waveguide high sensitivity and advantages, with improved resonator performance due to enhanced mode matching in racetrack bends. Depending on target bio-molecules, asymmetric slot resonators are very promising for small molecule sensing (dimensions <...
We present the simulation results of a method for the quantum cascade detectors (QCD) optical coupling. A metal grating was integrated with a QCD to convert normal-incident electromagnetic (EM) waves into non-normal, higher-order propagating wave (HOPW) and surface plasmon wave (SPW), which contribute to excite the bound-to-bound (BTB) intersubband transition of carriers in the QCD. The presented...
A visible-blind ultraviolet GaN back-illuminated avalanche photodiode with separate absorption and multiplication regions are simulated based on driftdiffusion equation. The current-voltage characteristics of the device have been numerically obtained. The result is in good agreement with the experimental data. It was found that the thickness of the multiplication layer is important to improve the...
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