Open AccessThe polarization field in Al-rich AlGaN multiple quantum wells
Author(s) -
Qiang Guo,
Ronny Kirste,
Seiji Mita,
James Tweedie,
Pramod Reddy,
Shun Washiyama,
M. Hayden Breckenridge,
Ramón Collazo,
Zlatko Sitar
Publication year - 2019
Publication title -
japanese journal of applied physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 129
eISSN - 1347-4065
pISSN - 0021-4922
DOI - 10.7567/1347-4065/ab07a9
Subject(s) - electric field , cladding (metalworking) , quantum well , piezoelectricity , nitride , materials science , polarization (electrochemistry) , quantum , condensed matter physics , stark effect , quantum confined stark effect , field (mathematics) , optoelectronics , chemistry , physics , optics , nanotechnology , composite material , laser , quantum mechanics , layer (electronics) , mathematics , pure mathematics
This paper investigates the quantum confined Stark effect in AlGaN multiple quantum well structures with a high Al content grown on single-crystalline AlN substrates. The quantitative relationship between the quantum well structure parameters, photogenerated carrier density, built-in electric field and ground-level emission is discussed. It is found that the electric field strength increases from 0.5 MV cm −1 to almost 3 MV cm −1 when the Al content in the quantum well barriers is increased from 65% to 100%, which is consistent with the theory of spontaneous and piezoelectric polarization in III-nitrides. In addition, the built-in electric field increases significantly with increasing barrier thickness. Based on these results, the electric field in an Al 0.55 Ga 0.45 N single quantum well with AlN cladding is predicted to be around 5 MV cm −1 .