Magnetic-optical transitions induced by twisted light in quantum dots

G. F. QUINTEIRO; D. E. REITER; KUHN, T.

Bariloche

Congreso; XXIII Latin American Symposium on Solid State Physics; 2018

Twisted light (TL) is light having a helical wave front. Such light exhibits several interesting features: Due to the azimuthal phase dependence a phase singularity occurs at the beam axis, leading to the name optical vortex. Furthermore, in addition to spin angular momentum (SAM) associated with the handedness of circular polarization, such light elds carry orbital angular momentum (OAM). Depending on the combination of SAM and OAM, TL beams may have strong eld components along the propagation direction or strong magnetic eldclose to the beam axis. The research in TL spans nowadays several areas of fundamental and applied physics [1]. Of particular interest is the interaction of a TL beam with matter, which opens up the possibility to address unusual transitions [2-3]. In this paper we focus on the interaction of TL with a semiconductor quantum dot (QD). QDs are discussed for many applications in optoelectronics and spintronics which, however, requires a precise control of the optically excited states. Here we will show that the interaction of a QD with TL having a strong magnetic component may be used for the excitation of specic light-hole (LH) excitons, which cannot easily be addressed by Conventional Gaussian beams or even twisted light with dominant electric elds.[1] D L Andrews, Structured light and its applications: An introduction to phase-structured beams and nanoscale optical forces (Academic Press), 2008[2] G F Quinteiro, D E Reiter and T Kuhn Phys. Rev. A 91 033808, 2015[3] G F Quinteiro, D E Reiter and T Kuhn Phys. Rev. A 95 012106, 2017