Optical transition dipoles in quasi-two dimensional semiconductor nanomaterials

Optical transition dipole moment is the key parameter in determining the interactions between an optical emitter and external electromagnetic fields. Understanding and having control over the transition dipole moments could lead to optoelectronic and photonic devices with unprecedented performance.[1,2] Transition dipole moments of materials can vary significantly depending on the materials’ band structures and compositions. In this work, we investigate the intrinsic optical transition dipole moments in quasi-two dimensional semiconductor nanomaterials, namely semiconductor nanoplatelets and quantum rings, to understand the influence of geometry and electronic structures on the transition dipole moments. Combining advanced quantum optical microscopy techniques with empirical tight-binding theory, we reveal strikingly different optical transition dipole properties in the two types of structures,[3,4] indicating the importance of material geometry and electronic structures in determining the transition dipole moments.

References:
1. T.-L. Wu et al. Nat. Photon. 2018, 12, 235-240
2. R. Chikkaraddy et al. Nature 2016, 535, 127-130
3. X. Ma et al. Nano Lett. 2018, 18, 4647-4652
4. N. F. Hartmann et al. Nat. Commun. 2019, 10, 3253