Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences Publications

Electronic transport

Discipline
Publication Year

Articles 1 - 4 of 4

Full-Text Articles in Physical Sciences and Mathematics

The Fast Recovery Dynamics Of A Quantum Dot Semiconductor Optical Amplifier, T. Piwonski, Guillaume Huyet, Et. Al. Mar 2009

The Fast Recovery Dynamics Of A Quantum Dot Semiconductor Optical Amplifier, T. Piwonski, Guillaume Huyet, Et. Al.

Physical Sciences Publications

We consider a rate equation model of a quantum dot semiconductor optical amplifier that takes into account carrier capture, escape, and Pauli blocking processes. We evaluate possible differences between phonon-assisted or Auger processes being dominant for recovery. An analytical solution which corresponds to phonon-assisted interaction is then used to accurately fit experimental recovery curves and allows an estimation of both the carrier capture and escape rates.


Intradot Dynamics Of Inas Quantum Dot Based Electroabsorbers, T. Piwonski, Jaroslaw Pulka, Gillian Madden, Guillaume Huyet, Et. Al. Jan 2009

Intradot Dynamics Of Inas Quantum Dot Based Electroabsorbers, T. Piwonski, Jaroslaw Pulka, Gillian Madden, Guillaume Huyet, Et. Al.

Physical Sciences Publications

The carrier relaxation and escape dynamics of InAs/GaAs quantum dot waveguide absorbers is studied using heterodyne pump-probe measurements. Under reverse bias conditions, we reveal differences in intradot relaxation dynamics, related to the initial population of the dots’ ground or excited states. These differences can be attributed to phonon-assisted or Auger processes being dominant for initially populated ground or excited states, respectively.


Phase Dynamics Of Inas/Gaas Quantum Dot Semiconductor Optical Amplifiers, T. Piwonski, Guillaume Huyet, Et. Al. Dec 2007

Phase Dynamics Of Inas/Gaas Quantum Dot Semiconductor Optical Amplifiers, T. Piwonski, Guillaume Huyet, Et. Al.

Physical Sciences Publications

The gain and phase dynamics of InAs∕GaAs quantum dot amplifiers are studied using single and two-color heterodyne pump probe spectroscopy. The relaxation of the wetting layer carrier density is shown to have a strong effect on the phase dynamics of both ground and excited state transients, while having a much weaker effect on the gain dynamics. In addition, the dynamical alpha factor may also display a constant value after an initial transient. Such behavior is strongly encouraging for reduced pattern effect operation in high speed optical networks.


Electron And Hole Dynamics Of Inas∕Gaasinas∕Gaas Quantum Dot Semiconductor Optical Amplifiers, I. O'Driscoll, T. Piwonski, C. F. Schleussner, J. Houlihan, G. Huyet, R. J. Manning Aug 2007

Electron And Hole Dynamics Of Inas∕Gaasinas∕Gaas Quantum Dot Semiconductor Optical Amplifiers, I. O'Driscoll, T. Piwonski, C. F. Schleussner, J. Houlihan, G. Huyet, R. J. Manning

Physical Sciences Publications

Single-color and two-color pump-probe measurements are used to analyze carrier dynamics in InAs∕GaAs quantum dot amplifiers. The study reveals that hole recovery and intradot electron relaxation occur on a picosecond time scale, while the electron capture time is on the order of 10ps. A longer time scale of hundreds of picoseconds is associated with carrier recovery in the wetting layer, similar to that observed in quantum well semiconductor amplifiers.