Silicon Based Colloidal Quantum Dot and Nanotube Lasers
Abstract
The most significant accomplishments in this project are: (a) demonstration of optically pumped quantum dot rolled-up microtube lasers with the minimum linewidth of 0.8 nm. After considering radiation, bending and substrate losses associated with the devices, the threshold carrier density is theoretically and experimentally derived to be inversely proportional to the diameter; (b) demonstration of InGaN/ GaN light emitting diodes and GaN single nanowire photonic crystal laser on silicon characterized by a lasing transition at lambda=371.3 nm with a linewidth of 0.55 nm. The threshold is observed at a pump power density of ~120 kW/cm2 and the spontaneous emission factor beta is estimated to be 0.08; (c) demonstration of lasing at ~1.55 micro m with PbSe quantum dots (QDs) on silicon. The measured electroluminescence exhibits a minimum linewidth of ~3.1 nm at a low injection current density of 3 A/cm2, and highly directional emission characteristics; (d) investigation of role of polariton-electron scattering and magnetic field on the performance characteristics of an electrically injected GaAs-based quantum well microcavity diode in the strong coupling. An electron gas is introduced in the quantum wells by modulation doping with silicon dopants. It is observed that polariton-electron scattering suppresses the relaxation bottleneck in the lower polariton branch.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2013
- Accession Number
- ADA575712
Entities
People
- Junseok Heo
- Pallab K. Bhattacharya
- Sishir Bhowmick
Organizations
- University of Michigan