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Thermophotovoltaic conversion using heat to generate electricity in photovoltaic cells based on the detraction of thermal radiation suffers from many engineering challenges. The focus of this paper is to study the nanostructure of AlGaAsSb for thermophotovoltaic energy conversion using lattice-matched heterostructures of GaSb-based materials in order to overcome the current challenges. The XAFS spectroscopy technique was used to analyze electronic structures and optical properties of GaSb, (Al, In) GaSbAs. The XAFS spectroscopy analysis showed a powerful decay at peak intensity that reveals to be related to a loss in Sb amount and light As atoms replaced in Sb atoms by 25%. Moreover, it was found that Al/In doped samples have highly symmetric data features (same atomic species substitution). The narrow direct bandgap energy, Eg of Al0.125Ga0.875Sb0.75As0.25 material raised (0.4–0.6 eV) compared to conventional photovoltaic cell bandgap energy (which is generally less than 0.4 eV) with weak absorption coefficients. The thermoelectric properties of AlGaAsSb computed via Botlztrap code showed that the electrons made up the majority of the charge carriers in AlGaAsSb. This nanostructure material exhibited a higher and acceptable figure of merit and demonstrated a promising thermoelectric material for solar thermophotovoltaic applications.

The electrical and optical properties of non-doped and Te doped 6.5 periods AlGaAsSb/AlAsSb Bragg mirrors on InP grown by MBE with different types of interfaces between ternary and quaternary layers are reported. The techniques employed were photoluminescence, refectivity and IxV measurements. The digital alloy gradient interface seems to be the best alternative to optimize conduction without significant refectivity losses.

The reflectivity of a Bragg mirror composed by materials of the antimony family (AlGaAsSb/AlAsSb), doped with tellurium, is analyzed in this work. The sample was prepared by molecular beam epitaxy (MBE) and the reflectivity was measured by Fourier Transform Infra-Red Spectroscopy (FTIR). In order to discuss the Bragg mirror properties, the experimental reflectivity is compared to a simulation of the reflectivity based on the matrix formalism.

São apresentadas as propriedades elétricas e ópticas de espelhos de Bragg com 6.5 períodos de AlGaAsSb/ AlAsSb não dopado e dopados com Te, sobre InP, crescidos por MBE com diferentes tipos de interface entre as camadas de material ternário e quaternário. As técnicas empregadas foram fotoluminescência, reflectividade e medições de IxV. A interface com liga digital em gradiente parece ser a melhor alternativa para otimizar condução elétrica sem perdas significativas da reflectividade.

Analisamos neste trabalho, a refletividade de um espelho de Bragg composto por materiais da família do antimônio (AlGaAsSb/AlAsSb) dopado com telúrio. As amostras foram preparadas através da técnica de epitaxia por feixe molecular MBE (Molecular Beam Epitaxy) e as medidas de refletividade pela técnica de espectroscopia de infravermelho por transformada de Fourier FTIR (Fourier Transform Infra- Red). Para discussão das propriedades do espelho de Bragg comparamos a refletividade obtida experimentalmente e uma simulação baseada no formalismo matricial.