Wednesday Colloquia

Invention, Development and Applications of Quantum Dot Lasers

by Prof. Pallab Bhattacharya (University of Michigan, Ann Arbor, USA)

Wednesday, August 14, 2019 from to (Asia/Kolkata)
at Lecture Theatre ( AG-66 )
The development of the quantum dot(QD) laser, from the early beginnings as a concept to its worldwide use in a number of important applications, will be described. A significant materials challenge was the reproducible creation of the "atom-like" quantum dots in a semiconductor matrix and the insertion of these QDs in a state-of-the-art laser heterostructure. The formation of coherent islands by strain relaxation and surface energy minimization in a lattice-mismatched heterostructure provided the pathway. The unique band structure and carrier dynamics in the QDs, phonon bottleneck and their effects on laser performance will be described. The characteristics of 1.1, 1.3, and 1.55 micron InAs/GaAs and InAs/InP QD lasers will be highlighted. Moreover, the properties of III-nitride visible to near-IR quantum dot and dot-in-nanowire array LEDs and diode lasers will be briefly discussed.