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Measurement and analysis of thermal parameters and efficiency of laser heterostructures and light-emitting diodes

100%

Bumai Y. A. , Vaskou A. S. , Kononenko V. K.

Metrology and Measurement Systems

2010

tom Vol. 17, nr 1

39-45

A thermal resistance characterization of semiconductor quantum-well heterolasers in the AlGaInAs-AlGaAs system (λst ≈ 0.8 μm), GaSb-based laser diodes (λst ≈ 2 μm), and power GaN light-emitting diodes (visible spectral region) was performed. The characterization consists in investigations of transient electrical processes in the diode sources under heating by direct current. The time dependence of the heating temperature of the active region of a source ΔT(t), calculated from direct bias change, is analyzed using a thermal RTCT equivalent circuit (the Foster and Cauer models), where RT is the thermal resistance and CT is the heat capacity of the source elements and external heat sink. By the developed method, thermal resistances of internal elements of the heterolasers and light-emitting diodes are determined. The dominant contribution of a die attach layer to the internal thermal resistance of both heterolaser sources and light-emitting diodes is observed. Based on the performed thermal characterization, the dependence of the optical power efficiency on current for the laser diodes is determined.

Asymmetric multiple quantum well heterostructure laser systems : conception, performance, and characteristics

100%

Kononenko V. K. , Afonenko A. A. , Manak I. S. , Nalivko S. V.

Opto-Electronics Review

2000

tom Vol. 8, No. 3

241-250

A new type of laser diodes and amplifiers based on asymmetric quantum-well heterostructures having active layers of different thickness and / or compositions has been considered. Bistable switching and regimes of regular radiation pulsation at two or three remote wavelengths in the range 790 - 850 nm in the GaAs-AlGaAs bi- and triple - quantum-well heterostructures are described. Influence of non-linear processes including gain suppression due to carrier heating on lasing regimes has been examined. Transformation of gain bands for TE and TM modes in dependence on the pump current has been studied for asymmetric four-quantum-well structures. The interval of tuning amplification wavelengths in the system reaches up to 70 nm.

Application of laser diodes and photodetectors on multiple-quantum wells at the hot-metal pyrometry

100%

Sen'kov A. G. , Firago V. A. , Kononenko V. K. , Christol P.

Pomiary Automatyka Kontrola

2007

tom R. 53, nr 9 bis

597--600

In the paper, the method of relative spectroreflectometry at using the infrared photodetectors with a wide diapason of the spectral photosensitivity is suggested. Methodical errors at exponential and power dependencies of the emissivity of an object on the wavelength are analysed. Possible design of a pyrometer for measurements of temperature of hot metals is described and attractiveness of quantum-well laser diodes and superlattice photodetectors based on the GaSb compounds is discussed.

W pracy zaproponowano metodę spektrofotometrii porównawczej z wykorzystaniem fotodetektorów podczerwieni o szerokim zakresie czułości spektralnej. Określono błędy systematyczne związane z wykładniczą i kątową zależnością od długości fali i współczynnika emisyjności obiektów. Przedstawiono jedną z możliwych konstrukcji pirometru do pomiaru rozgrzanych metali. Dyskutuje się również możliwość zastosowania diod laserowych o rozmiarach kwantowych oraz fotodetektorów zbudowanych w oparciu o złącza GaSb.

Optical gain in one-dimensional photonic band gap structures with n-i-p-i crystal layers

88%

Nefedov I. S. , Gusyatnikov V. N. , Marciniak M. , Kononenko V. K. , Ushakov D. V.

Journal of Telecommunications and Information Technology

2002

tom nr 1

60-64

The gain enhancement in a layered periodic photonic band gap structure containing active medium based on GaAs n-i-p-i superlattices separated by A1GaAs layers is analyzed. The dependences of extinction coefficient and refractive index on excitation level and wavelength are presented. Transmission characteristics of a probe light versus excitation level are calculated. It is shown that the threshold of generation can be essentially reduced if the wavelength of probe light falls to the band gap edge.