Quantum Dot Laser

Year: 
2014
Ranking: 
Entrant
Artist: 
Alan Y. Liu
Lab: 
MBE Lab (Gossard/Bowers group)

Description

This is a touched up AFM rendering of semiconductor InAs quantum dots grown on GaAs by Molecular Beam Epitaxy (MBE). With each dot spanning only a few nanometers in any direction, tens of billions of them can comfortably fit in an area the size of a penny. Due to their small size, they are quantum mechanical in nature and possess discrete quantum confined energy levels - a real life representation of the 'finite potential well' problem from introductory quantum mechanics courses. In the presence of external stimuli such as photo-excitation or electrical carrier injection, each dot is able to emit photons with wavelengths corresponding to their intrinsic quantum confined energy levels. When placed in a resonant cavity with sufficient external stimuli, the dots become in sync with each-other and emit a coherent laser beam composed of the billions of photons from each individual dot, truly becoming greater than the sum of their parts through this collective lasing action.

CSEP CNSI Schuller Lab UCSB