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Updated: Apr 6, 2026
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Biexciton Binding of Dirac fermions Confined in Colloidal Graphene Quantum Dots
Cheng Sun1, Florian Figge1, Isil Ozfidan2
1†Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, United States.
Abstract:
We present transient absorption measurements and microscopic theory of biexciton binding in triangular colloidal graphene quantum dots consisting of 168 sp(2)-hybridized C atoms. We observe optical transitions from the lowest orbitally dark singlet exciton states to states below the energy of an unbound dark+bright singlet-exciton pair. Through microscopic calculations of the low-energy exciton and biexciton states via tight-binding, Hartree-Fock, and configuration interaction methods, the spectra reveal a biexciton consisting primarily of a dark-bright singlet-pair bound by ∼0.14 eV.
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