Abstract

A laser structure is studied, which exploits tunneling-injection of electrons and holes into quantum dots (QDs) from two separate quantum wells (QWs). An extended theoretical model is developed allowing for out-tunneling leakage of carriers from QDs into the opposite-to-injection-side QWs (electrons into the p-side QW and holes into the n-side QW). Due to out-tunneling leakage, parasitic recombination of electron-hole pairs occurs outside QDs – in the QWs and optical confinement layer. The threshold current and the characteristic temperature are shown to be mainly controlled by the recombination in the QWs. Even in the presence of out-tunneling from QDs and recombination outside QDs, a tunneling-injection laser shows potential for significant improvement of temperature stability of the threshold current — the characteristic temperature remains very high (above 300 K at room temperature) and not significantly affected by the QD size fluctuations.

 

Biography

Dae-Seob Han received his B.S. degree in MSE from Chungnam National University in 2000 and M.S. degree in MSE from Gwangju Institute of Science and Technology in 2005. He worked in electronic-packaging research center at Samsung Company for 3 years and in information electronic materials group at LG Company for 2 years. He is currently pursuing his Ph.D. degree under the direction of Prof. Asryan. His area of study is semiconductor light-emitting devices with a quantum-confined active region.