Figure 1: Quantum dot—pillar cavity device and its characterization by coherent reflection spectroscopy.
From: Macroscopic rotation of photon polarization induced by a single spin
(a) Scanning electron microscope view of various micropillar devices. Yellow triangles denote the positions of the deterministically coupled QDs. Scale bar, 5 μm. (b) Sketch of the QD micropillar device and corresponding interaction processes (red circle, internal QD-cavity coupling; blue arrows, cavity damping; green arrow, QD dephasing). (c,d) Device reflectivity as a function of the laser photon energy, for two orthogonal linear polarizations X and Y. The two modes are nearly polarization degenerate. (e) Zoom from c, focusing at the bottom of the reflectivity dip. The observed peak is a signature of a QD-induced transition resonant at 20 K with the X-polarized mode. The peak amplitude is referred to as the QD-induced reflectivity variation ΔRQD.
