Back to results
US 5,692,003 AGranted
Quantum-dot cascade laser
AssigneeNEC Research Institute, Inc.
InventorsNed Scott Wingreen, Charles A. Stafford
Life of this patent
Estimating the term…
Abstract
A quantum-dot cascade laser which eliminates single phonon decays associated with quantum-well devices. The elimination of single phonon decays is realized by a three-dimensional confinement resulting in a several-order-of-magnitude reduction in the threshold current. Dot size, dot density and dot uniformity requirements are presented along with several embodiments.
Claims9
A quantum-dot cascade laser device comprising:
- a substrate layer having an electrical contact;
- one or more double-dot layers overlying said substrate, each of said double-dot layers having:
- an array of double-dots, each having a volume, surrounded by and separated from one another by a semiconductor barrier such that each one of said double-dots is sufficiently-spaced from one another to provide an effective dot density, wherein a double-dot comprises two quantum dots in sufficiently close proximity to allow quantum mechanical tunneling of an electron between the two quantum dots and a quantum dot is a sufficiently small volume of a semiconductor material surrounded on all sides by another suitable material;
- and
- a contact layer having an electrical contact and overlying said double-dot layers whereby by the passage of current flow through the device laser operation may be achieved.
2 more elements
Dependencies are inferred from the claim text.