High-efficiency electron-beam-pumped sub-240-nm ultraviolet emitters based on ultra-thin GaN/AlN multiple quantum wells grown by plasma-assisted molecular-beam epitaxy on c-Al2O3.

Autor: Valentin N. Jmerik, Dmitrii V. Nechaev, Alexey A. Toropov, Evgenii A. Evropeitsev, Vladimir I. Kozlovsky, Victor P. Martovitsky, Sergey Rouvimov, Sergey V. Ivanov
Zdroj: Applied Physics Express; Sep2018, Vol. 11 Issue 9, p1-1, 1p
Abstrakt: We report the internal structures and emission properties of GaN/AlN single- and multiple-quantum-well (QW) heterostructures with well widths of dw = 1–4 monolayers (MLs), grown by plasma-assisted molecular-beam epitaxy on c-sapphire at metal-rich conditions and low temperatures (∼700 °C). The formation of plane QWs with abrupt symmetrical interfaces is confirmed by both scanning transmission electron microscopy and X-ray diffraction analysis. Pulse-scanning and continuous-wave output powers of 150 and 28 mW, respectively, at a peak emission wavelength of 235 nm were achieved at 300 K in an electron-beam-pumped deep-ultraviolet (1.5 ML-GaN/5.5 nm-AlN)360 multiple-QW emitter with a maximum efficiency of 0.75%. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index