Ostendo Technologies, Inc.

The State University of New York

Maxion Technologies, Inc.

University of Texas System

Mikhail V Kisin

Hussein S El-Ghoroury

Chih-Li Chuang

Yea-Chuan Milton Yeh

Jyh-Chia Chen

Serge Luryi

Gregory L Belenky

John D Bruno

Richard L Tober

Sergey Suchalkin

Leon Shterengas

Mikhail A Belkin

Disclosed herein are multi-layered optically active regions for semiconductor light-emitting devices (LEDs) that incorporate intermediate carrier blocking layers, the intermediate carrier blocking layers having design parameters for compositions and doping levels selected to provide efficient control over the carrier injection distribution across the active regions to achieve desired device injection characteristics. Examples of embodiments discussed herein include, among others: a multiple-quantum-well variable-color LED operating in visible optical range with full coverage of RGB gamut, a multiple-quantum-well variable-color LED operating in visible optical range with an extended color gamut beyond standard RGB gamut, a multiple-quantum-well light-white emitting LED with variable color temperature, and a multiple-quantum-well LED with uniformly populated active layers.

Multi-color light emitting structures with controllable emission color

Light emitting structures with multiple uniformly populated active layers

Light emitting structures with selective carrier injection into multiple active layers

White light emitting structures with controllable emission color temperature

The present invention provides a QCL device with an electrically controlled refractive index through the Stark effect. By changing the electric field in the active area, the energy spacing between the lasing energy levels may be changed and, hence, the effective refractive index in the spectral region near the laser wavelength may be controlled.

Quantum cascade lasers with electrically tunable emission wavelengths

A semiconductor light source comprises a substrate, lower and upper claddings, a waveguide region with imbedded active area, and electrical contacts to provide voltage necessary for the wavelength tuning. The active region includes single or several heterojunction periods sandwiched between charge accumulation layers. Each of the active region periods comprises higher and lower affinity semiconductor layers with type-II band alignment. The charge carrier accumulation in the charge accumulation layers results in electric field build-up and leads to the formation of generally triangular electron and hole potential wells in the higher and lower affinity layers. Nonequillibrium carriers can be created in the active region by means of electrical injection or optical pumping. The ground state energy in the triangular wells and the radiation wavelength can be tuned by changing the voltage drop across the active region.

Semiconductor light source with electrically tunable emission wavelength

Growing community of inventors

Carlsbad, CA, United States of America

Mikhail V Kisin