Intersubband optics in GaN-based nanostructures - physics and applications

In this paper we review the recent achievements in terms of GaN/AlGaN-based intersubband (ISB) physics and devices. We first discuss the design issues and in particular the band bending effect and its influence on the ISB absorption. We then illustrate recent achievements in terms of III-nitride ISB devices with special emphasis on electro-optical modulator and a quantum cascade detector operating in the near-infrared. We show that these devices offer high frequency response at telecommunication wavelengths.