skip to main content

SciTech ConnectSciTech Connect

Title: Self-screening of the quantum confined Stark effect by the polarization induced bulk charges in the quantum barriers

InGaN/GaN light-emitting diodes (LEDs) grown along the polar orientations significantly suffer from the quantum confined Stark effect (QCSE) caused by the strong polarization induced electric field in the quantum wells, which is a fundamental problem intrinsic to the III-nitrides. Here, we show that the QCSE is self-screened by the polarization induced bulk charges enabled by designing quantum barriers. The InN composition of the InGaN quantum barrier graded along the growth orientation opportunely generates the polarization induced bulk charges in the quantum barrier, which well compensate the polarization induced interface charges, thus avoiding the electric field in the quantum wells. Consequently, the optical output power and the external quantum efficiency are substantially improved for the LEDs. The ability to self-screen the QCSE using polarization induced bulk charges opens up new possibilities for device engineering of III-nitrides not only in LEDs but also in other optoelectronic devices.
Authors:
; ; ; ; ; ; ; ;  [1] ;  [1] ;  [2]
  1. LUMINOUS Centre of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)
  2. (Turkey)
Publication Date:
OSTI Identifier:
22299925
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 24; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTAL GROWTH; DIFFUSION BARRIERS; ELECTRIC FIELDS; GALLIUM NITRIDES; HOTELS; INDIUM NITRIDES; INTERFACES; LIGHT EMITTING DIODES; ORIENTATION; POLARIZATION; QUANTUM EFFICIENCY; QUANTUM WELLS; SCREENING; STARK EFFECT