Long lifetimes of quantum-dot intersublevel transitions in the terahertz range.

A voltage tunable quantum dot photodetector for terahertz detection

A voltage tunable quantum dot (QD) photodetector for terahertz detection based on intersublevel transitions is proposed. The intersublevels are formed by the lateral electrical confinement applied on quantum wells and the transitions between them can be strongly tuned by the confinement. Under normal incidence, the peak detection wavelengths can be tuned from ∼50 to ∼90μm (6.0 to ∼3.3 THz) with...

Modeling of an electrically tunable quantum dot photodetector for terahertz detection

The terahertz region (1-10 THz) has potential applications in many areas, such as chemical sensing, medical imaging and free-space optical communications. With the demonstration of terahertz sources, it is quite necessary to develop the detection technology in terahertz. Here we propose an electrically tunable quantum dot infrared photodetector to detect the terahertz region. The proposed detec...

A Quantum Dot Microcavity Terahertz Laser

We discuss a THz laser device based on a semiconductor quantum dot (QD) gain medium, where the lasing occurs through discrete conduction states. An ensemble of QDs is selectively placed in a high quality cavity, called a microdisk, which is resonant with a terahertz intersublevel QD transition. We simulate the rate equations goveming iasing and discuss a variety of processes affecting lasing in...

Effect of quantum dot size and size distribution on the intersublevel transitions and absorption coefficients of III-V semiconductor quantum dot

Room temperature midinfrared electroluminescence from InAs quantum dots

We demonstrate room temperature midinfrared electroluminescence from intersublevel transitions in self-assembled InAs quantum dots. The dots are grown in GaAs/AlGaAs heterostructures designed to maximize current injection into dot excited states while preferentially removing electrons from the ground states. As such, these devices resemble quantum cascade lasers. However, rigorous modeling of c...