Infrared transmission spectroscopy of charge carriers in self-assembled InAs quantum dots under surface electric fields

J Phys Condens Matter. 2014 Dec 17;26(50):505801. doi: 10.1088/0953-8984/26/50/505801.


We present a study on the intersublevel spacings of electrons and holes in a single layer of InAs self-assembled quantum dots. We use Fourier transform infrared transmission spectroscopy via a density chopping scheme for direct experimental observation of the intersublevel spacings of electrons without any external magnetic field. Epitaxial, complementary-doped and semi-transparent electrostatic gates are grown within the ultra high vacuum conditions of molecular beam epitaxy to voltage-tune the device, while a two dimensional electron gas (2DEG) serves as a back contact. Spacings of the hole sublevels are indirectly calculated from the photoluminescence spectrum by using a simple model given by Warburton et al [1]. Additionally, we observe that the intersubb and resonances of the 2DEG are enhanced due to the quantum dot layer on top of the device.

Publication types

  • Research Support, Non-U.S. Gov't