posted on 2022-01-24, 16:07authored byNiharika Gupta, Hyungjin Kim, Nima Sefidmooye Azar, Shiekh Zia Uddin, Der-Hsien Lien, Kenneth B. Crozier, Ali Javey
The mid-wave infrared (MWIR) wavelength
range plays a central role
in a variety of applications, including optical gas sensing, industrial
process control, spectroscopy, and infrared (IR) countermeasures.
Among the MWIR light sources, light-emitting diodes (LEDs) have the
advantages of simple design, room-temperature operation, and low cost.
Owing to the low Auger recombination at high carrier densities and
direct bandgap of black phosphorus (bP), it can serve as a high quantum
efficiency emitting layer in LEDs. In this work, we demonstrate bP-LEDs
exhibiting high external quantum efficiencies and wall-plug efficiencies
of up to 4.43 and 1.78%, respectively. This is achieved by integrating
the device with an Al2O3/Au optical cavity,
which enhances the emission efficiency, and a thin transparent conducing
oxide [indium tin oxide (ITO)] layer, which reduces the parasitic
resistance, both resulting in order of magnitude improvements to performance.