• ESFANDIAR RAJAEI

Articles written in Pramana – Journal of Physics

• Effect of temperature on $In_{x}Ga_{1−x}As/GaAs$ quantum dots

In this paper, the strain, band-edge, and energy levels of pyramidal $In_{x}Ga_{1−x}As/GaAs$ quantum dots are investigated by 1-band effective mass approach. It is shown that while temperature has no remarkable effect on the strain tensor, the band gap lowers and the radiation wavelength elongates by increasing temperature. Also, band gap and energy do not linearly decrease by temperature rise. Our results appear to agree with former researches. This can be used in designing laser devices and sensors when applied in different working temperatures. Furthermore, when the device works for a long time, self-heating occurs which changes the characteristics of the output.

• Impact of optical gain broadening on characteristics of response function in the presence and absence of tunnelling injection for quantum dot semiconductor lasers

In this paper, the dynamics of QD semiconductor lasers is investigated numerically. Large and small signal modulations for various inhomogeneous broadenings have been studied. Computationally, we have solved the rate equation for two-state InAs QD semiconductor lasers and the effect of inhomogeneous broadening on response function and output power due to variation of QD parameters have been investigated in the presence and absence of tunnelling. Also, we have studied these effects on optical gain and output power. We have shown that tunnelling injection enhances the efficiency of the semiconductor laser.

• Pramana – Journal of Physics

Volume 96, 2022
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Continuous Article Publishing mode

• Editorial Note on Continuous Article Publication

Posted on July 25, 2019