Far-infrared photoconductivity in self-organized InAs quantum dots

Abstract

We report far-infrared photoconductivity in self-organized InAs/GaAs quantum dots grown by molecular beam epitaxy. Through use of a Fourier transform infrared spectrometer, a photoconductivity signal peaked at 17 μm is observed from a n–i–n detector structure with doped InAs quantum dots in the intrinsic region. Comparison of photoluminescence and band-to-band photocurrent absorption spectra suggests the far-infrared response is due to intersubband transitions in the quantum dots.