1 research outputs found
Tunable Anisotropic Photon Emission from Self-Organized CsPbBr<sub>3</sub> Perovskite Nanocrystals
We
report controllable anisotropic light emission of photons originating
from vertically aligned transition dipole moments in spun-cast films
of CsPbBr<sub>3</sub> nanocubes. By depositing films of nanocrystals
on precoated substrates we can control the packing density and resultant
radiation pattern of the emitted photons. We develop a technical framework
to calculate the average orientation of light emitters, i.e., the
angle between the transition dipole moment vector (TDM) and the substrate.
This model is applicable to any emissive material with a known refractive
index. Theoretical modeling indicates that oriented emission originates
from an anisotropic alignment of the valence band and conduction band
edge states on the ionic crystal lattice and demonstrates a general
path to model the experimentally less accessible internal electric
field of a nanosystem from the photoluminescent anisotropy. The uniquely
accessible surface of the perovskite nanoparticles allows for perturbation
of the normally isotropic emissive transition. The reported sensitive
and tunable TDM orientation and control of emitted light will allow
for applications of perovskite nanocrystals in a wide range of photonic
technologies inaccessible to traditional light emitters