Encapsulated CsPbBr3 quantum dots with asymmetric chiral magneto-optoelectronic responses

Abstract

Quantum emitters having non-trivial spin polarizations are highly demanded for chiral quantum devices and quantum photonic technologies. Here we investigate the magneto photoluminescence spectroscopy of perovskite quantum dots encapsulated in silica and report an observation of chiral magneto optoelectronic responses. The encapsulation stabilizes the emission and also increases the lattice distortion that alters the exciton properties. As a result, asymmetric behaviors for the degree of circular polarization to the positive and negative magnetic fields are observed from both bright and dark states in the quantum dot. The magneto optoelectronic responses further demonstrate the state mixture between bright and dark excitons, which well explains the chiral features of the quantum dot. The chirality and magnetic field manipulation in the encapsulation environment pave the way to apply them in chiral quantum photonic devices with operational stability. Encapsulated perovskite quantum dots provide quantum emitters with high yield and operational stability. The authors reveal the chiral magneto optical response of these quantum dots and pave the way to applications in chiral quantum photonic devices.