Spectrometry and Performance Characteristics of a BGO–ФЭУ-165 Scintiblock in a Temperatire Range of +25 to –140°C

The possibility of the joint operation of a -165 photomultiplier based on microchannel plates and a BGO crystal, which are cooled to a temperature required for the operation of a semiconductor Ge detector, is investigated taking into account the temperature dependence of proper PMT characteristics. The system was cooled from room temperature to –140°C for 8 h. The limiting temperature at which the PMT holds its serviceability was determined, and the temperature changes in the spectroscopic characteristics of the system (the energy resolution and signal-to-noise ratio) were studied.     

Flip-chip LEDs with deep mesa emitting at 4.2 µm

The spectral, current-voltage, and emission-current characteristics under forward and reverse biases, and the near-field emission pattern of flip-chip LEDs based on heterostructures with an InAsSb active layer (emission wavelength of 4.2 μm at 300 K) and a mesa of 40–50 μm in depth and 240 μm in diameter are analyzed. The possibility of raising the emission output by varying the configuration of the structure and selecting the optimal operation mode dependently on the working temperature are discussed. Original Russian Text ? N.V. Zotova, N.D. Il’inskaya, S.A. Karandashev, B.A. Matveev, M.A. Remennyi, N.M. Stus’, 2006, published in Fizika i Tekhnika Poluprovodnikov, 2006, Vol. 40, No. 6, pp. 717–723.     

Negative luminescence at 3.9 µm in InGaAsSb-based diodes

Current-voltage characteristics, as well as spectral and power-current characteristics, for the emission of InAsSbP/InGaAsSb double-heterostructure diodes grown on InAs substrates were measured under forward and reverse biases in the temperature range of 25–90°C. It was shown that the conversion efficiency for negative luminescence, which occurs due to the extraction of charge carriers from the regions adjacent to the p-n junction at temperatures ～90°C, is higher than the conversion efficiency for electroluminescence. Narrowing of the negative luminescence spectra in diodes with a built-in cavity was observed.