Deterministic optical polarisation in nitride quantum dots at thermoelectrically cooled temperatures.

ABSTRACT: We report the successful realisation of intrinsic optical polarisation control by growth, in solid-state quantum dots in the thermoelectrically cooled temperature regime (?200?K), using a non-polar InGaN system. With statistically significant experimental data from cryogenic to high temperatures, we show that the average polarisation degree of such a system remains constant at around 0.90, below 100?K, and decreases very slowly at higher temperatures until reaching 0.77 at 200?K, with an unchanged polarisation axis determined by the material crystallography. A combination of Fermi-Dirac statistics and k·p theory with consideration of quantum dot anisotropy allows us to elucidate the origin of the robust, almost temperature-insensitive polarisation properties of this system from a fundamental perspective, producing results in very good agreement with the experimental findings. This work demonstrates that optical polarisation control can be achieved in solid-state quantum dots at thermoelectrically cooled temperatures, thereby opening the possibility of polarisation-based quantum dot applications in on-chip conditions.

SUBMITTER: Wang T 

PROVIDER: S-EPMC5608953 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature