Mirror-symmetric magnetic circularly polarized luminescence from CdS/ZnS core-shell quantum dots: Faraday effect in the photoexcited state

Highlights: • Achiral CdS/ZnS quantum dots show magnetic circularly polarized luminescence (MCPL). • The sign of the MCPL depended on the direction of the magnetic field. • The MCPL behavior of bare and functionalized quantum dots was similar. • The quantum dots exhibited MCPL both in the solid and solution states. Ambidextrous magnetic circularly polarized luminescence (MCPL) is observed for the first time from five kinds of achiral soluble diamagnetic CdS/ZnS core-shell quantum dots in toluene and aqueous solutions, dispersed in poly(methyl methacrylate) film, and as solid powders when subjected to external north-up and south-up magnetic fields of 1.6 Tesla. The magnitude of MCPL, g_MCPL, is on the order of |g_MCPL| = 10^–3 between 400 and 460 nm. The sign of these MCPL spectra is controlled solely by the direction of the magnetic field.