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The creation of a sustainable energy generation, storage, and distribution infrastructure represents a global grand challenge that requires massive transnational investments in the research and development of energy technologies that will provide the amount of energy needed on a sufficient scale and timeframe with minimal impact on the environment and have(More)
One of the crucial steps in the design of an integrated circuit is the minimization of heating and temperature non-uniformity. Current temperature calculation methods, such as finite element analysis and resistor networks have considerable computation times, making them incompatible for use in routing and placement optimization algorithms. In an effort to(More)
Design of passive ring-coupled lasers based on InGaAsP waveguides is investigated using beam propagation method. Mode coupling, propagation loss due to bending, and scattering loss from waveguide sidewall roughness are taken into account. By compromising threshold gain, linewidth and side-mode suppression ratio (SMSR), suitable waveguide width and coupling(More)
We investigate thermal effects in widely tunable laser transmitters based on an integrated single chip design. The chip contains a sampled-grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with a semiconductor optical amplifier (SOA) and an electroabsorption modulator (EAM). The thermal impedance of the ridge structure is(More)
Temperature strongly affects output power and peak wavelength characteristics of active optoelectronic devices. In this paper we describe how thermoreflectance imaging technique can be used to obtain thermal maps of photonic devices under operation. Submicron spatial resolution and <0.1C temperature resolution has been achieved. Temperature non-uniformity(More)
We present theoretically that the cross-plane Seebeck coefficient of InGaAs/ InGaAlAs III–V semiconductor superlattices can be significantly enhanced through miniband transport at low temperatures. The miniband dispersion curves are calculated by self-consistently solving the Schrödinger equation with the periodic potential, and the Poisson equation taking(More)
We characterize cross-plane and in-plane Seebeck coefficients for ErAs:InGaAs/InGaAlAs superlattices with different carrier concentrations using test patterns integrated with microheaters. The microheater creates a local temperature difference, and the cross-plane Seebeck coefficients of the superlattices are determined by a combination of experimental(More)
Metal/semiconductor superlattices have the potential for a high thermoelectric figure of merit. The thermopower of these structures can be enhanced by controlling the barrier height using high-energy electron filtering. In addition, phonon scattering at interfaces can reduce the lattice contribution to the thermal conductivity. In this paper, we present(More)
Recent experimental results have shown that adding nanoparticles inside a bulk material can enhance the thermoelectric performance by reducing the thermal conductivity and increasing the Seebeck coefficient. In this paper we investigate electron scattering from nanoparticles using different models. We compare the results of the Born approximation to that of(More)