Publications by authors named "Henk T C Stoof"
Article Synopsis
- Colloidal nanocrystals have advanced in size and surface properties, leading to potential applications in optoelectronics and quantum materials.
- The study focuses on two-dimensional BiSe crystals with controlled thickness, exploring the transition of a topological insulator as it shifts from three to two dimensions.
- Results reveal an 8 nm wide edge state around specific BiSe structures and discuss its characteristics using advanced theoretical models, also suggesting the possible state density for future devices.
We analyze the topology, dispersion, and optical selection rules of bulk Wannier excitons in nanosheets of BiSe, a topological insulator in the family of the bismuth chalcogenides. Our main finding is that excitons also inherit the topology of the electronic bands, quantified by the skyrmion winding numbers of the constituent electron and hole pseudospins as a function of the total exciton momentum. The excitonic bands are found to be strongly indirect due to the band inversion of the underlying single-particle model.
View Article and Find Full Text PDFWe studied the initial nature and relaxation of photoexcited electronic states in CdSe nanoplatelets (NPLs). Ultrafast transient optical absorption (TA) measurements were combined with the theoretical analysis of the formation and decay of excitons, biexcitons, free charge carriers, and trions. In the latter, photons and excitons were treated as bosons and free charge carriers as fermions.
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