Carrier Localization in Gallium Nitride

Carrier Localization in Gallium Nitride

In wide bandgap GaN a large number of interesting and important scientific questions remain to be answered. For example, the large free electron concentration reaching 1019 to 1020 cm-3 in nominally undoped material are ascribed to intrinsic defects because no chemical impurity has been found at such high concentrations. According to theoretical models a nitrogen vacancy acts as a donor but its...

Carrier localization of as-grown n-type gallium nitride under large hydrostatic pressure.

A quantitative study of the carrier localization in GaN under large hydrostatic pressure is presented using infrared reflection and Raman spectroscopy. The free-carrier concentration in as-grown n-type GaN crystals is determined optically from the phonon-plasmon–coupled mode and an analysis of the dielectric function. A strong decrease from 1310 cm at ambient pressure to only 3310 cm at a press...

Gallium Nitride Photoconductive Detectors

Since 1994, the Applied Physics Laboratory has been collaborating with NASA Goddard Space Flight Center to develop photodetectors based on gallium nitride and aluminum gallium nitride material produced in the Milton S. Eisenhower Research and Technology Development Center. This article describes the results of our collaboration and highlights the development of gallium nitride photodetectors wi...

Single gallium nitride nanowire lasers.

There is much current interest in the optical properties of semiconductor nanowires, because the cylindrical geometry and strong two-dimensional confinement of electrons, holes and photons make them particularly attractive as potential building blocks for nanoscale electronics and optoelectronic devices, including lasersand nonlinear optical frequency converters. Gallium nitride (GaN) is a wide...

Gallium Nitride Nanowire Electromechanical Resonators