P-doped Quantum Dots for Optoelectronic Devices

Introduction

The invention covers the introduction of p-type impurities into the active material of III-V nanostructures called quantum dots (QDs) for the purpose of improving optoelectronic device performance. The new discovery is that closely spaced (in energy) discrete electronic levels connected to the valence band of the III-V semiconductor but associated with the nanostructure limit laser performance, and that this limitation is removed by the introduction of certain level of p-type impurities into barrier layers around the QDs, so that excess holes created by these impurities are captured within the QDs.

Invention Description

This invention introduces a precise level of p-type impurities in the QD barrier layers to fill their discrete valence levels with an excess of equilibrium holes. The introduction of p-type impurities into the QD barrier layers are presently not used in these lasers.

Benefits

• Large increase in the optical gain for a given injection current
• Large increase in the differential gain to improve modulation speed of the laser

Market Potential/Applications

Any optolectronic device based on QDs for optical gain, such as switches and optical amplifiers

IP Status

One U.S. Patent Issued.

UT Researcher

• Dennis G. Deppe, Ph.D., Department of Electrical and Computer Engineering, The University of Texas at Austin
  
• Oleg B. Shchekin, Department of Electrical and Computer Engineering, The University of Texas at Austin

Contact:

University os texas,
Austin, USA
Website : www.otc.utexas.edu