Magnetic-field interaction of spatially confined quantum-well exciton-polaritons
Rahimi-Iman, A.; Schneider, C.; Fischer, J.; Holzinger, S.; Amthor, M.; Worschech, L.; Reitzenstein, Stephan; Höfling, S.; Forchel, A.; Kamp, M.
We report on pronounced magneto-optical effects of trapped polariton modes in a single InGaAs quantum well microresonator with a lithographically defined modulation of the cavity length. In our optical polariton traps with diameters ranging from 1 to 10 μm, a confinement potential of 7.5 meV is achieved. In magnetic-field dependent experiments, a diamagnetic shift and a Zeeman splitting of the trap-modes are observed which confirms that the polaritonic nature of the quantized emission modes are preserved even for traps as small as 1 μm. Furthermore, focusing on theoretical estimates using a simple model, we have identified a clear correlation between the polaritons' magnetic response and their excitonic fraction, corresponding to the Hopfield coefficients of the composite particles.
