Platform Renewal - Optical gain and recombination in structured materials
Lead Research Organisation:
Cardiff University
Department Name: School of Physics and Astronomy
Abstract
This proposal is to support a group activity based on excellence and unique capabilities in the measurement of fundamental optical processes in materials and device structures. We aim to achieve deeper understanding of the physics of light-matter interactions, embracing colloidal and biological systems, and to enable advances in device concepts to be made, particularly by integration of functional and structured materials, and integration with living systems.This activity is strongly linked, in two way interactions, to a series of intermediate and end users ensuring relevence and that our work benefits the wider community.
Organisations
Publications
Tsvid G
(2008)
Spontaneous Radiative Efficiency and Gain Characteristics of Strained-Layer InGaAs-GaAs Quantum-Well Lasers
in IEEE Journal of Quantum Electronics
Sobiesierski A
(2011)
Comprehensive Semiconductor Science and Technology
Smowton P
(2008)
Origin of Temperature-Dependent Threshold Current in p-Doped and Undoped In(Ga)As Quantum Dot Lasers
in IEEE Journal of Selected Topics in Quantum Electronics
Ridha P
(2010)
Polarization Properties of Columnar Quantum Dots: Effects of Aspect Ratio and Compositional Contrast
in IEEE Journal of Quantum Electronics
O'Driscoll I
(2012)
Effect of proton bombardment on InAs dots and wetting layer in laser structures
in Applied Physics Letters
O'Driscoll I
(2010)
Many-body effects in InAs/GaAs quantum dot laser structures
in Applied Physics Letters
O'Driscoll I
(2010)
Random Population of Quantum Dots in InAs-GaAs Laser Structures
in IEEE Journal of Quantum Electronics
O'Driscoll I
(2009)
Low-Temperature Nonthermal Population of InAs-GaAs Quantum Dots
in IEEE Journal of Quantum Electronics
Naidu D
(2010)
The measured dependence of the lateral ambipolar diffusion length on carrier injection-level in Stranski-Krastanov quantum dot devices
in Journal of Applied Physics
| Description | We have experimentally demonstrated and modelled the transition from a fully random distribution of carrier in a coupled quantum dot - wetting layer system at 20K through a non-thermal distribution at intermediate temperatures to a fully thermal distribution above room temperature. We have demonstrated that the associated gain spectrum width controls and is the limiting factor in pulse duration in modelocked lasers fabricated from this material We have demonstrated the degree to which carrier lifetime is affected by proton bombardment and demonstrated this as a way of optimising the recovery time of a saturable absorber in an integrated mode locked laser. We have explained the origin of the temperature dependence of threshold current density in quantum dot lasers. We have measured the ambipolar diffusion length in active quantum dot material. We have demonstrated deep etched gratings and their use as reflectors in the GaInP / AlGaInP system |
| Exploitation Route | Improve the performance of short pulse lasers and integrated systems at high temperature. As a whole this work illustrates the advantages and parameter space of these quantum dot materials for use in the further integration of optoelectronics and more highly functionalised devices and points towards the possibility of the future integration of photonics and silicon based electronics. |
| Sectors | Digital/Communication/Information Technologies (including Software),Healthcare |
| Description | Device designs used as generic structures for customers wanting to try out quality |
| First Year Of Impact | 2009 |
| Sector | Manufacturing, including Industrial Biotechology |
| Impact Types | Economic |
| Description | Cardiff University |
| Amount | £25,251 (GBP) |
| Funding ID | Cardiff Partnership fund |
| Organisation | Cardiff University |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 05/2012 |
| End | 05/2013 |
| Description | Cardiff University |
| Amount | £25,251 (GBP) |
| Funding ID | Cardiff Partnership fund |
| Organisation | Cardiff University |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 05/2012 |
| End | 04/2013 |
| Description | Impact Acceleration Account |
| Amount | £56,299 (GBP) |
| Funding ID | EP/503988/1 |
| Organisation | Engineering and Physical Sciences Research Council (EPSRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 10/2013 |
| End | 09/2014 |