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Quantum Coupling of Two Atomic Defects in a Carbon Nanotube Semiconductor
Jacob Fortner1,2, YuHuang Wang1,2
1Chemical Physics Program, University of Maryland, College Park, Maryland 20742, United States.
Abstract:
Chemical defects can create organic color centers in the graphitic lattice of single-walled carbon nanotubes. However, the underlying physics remains somewhat of a mystery. Here we show that two sp3 atomic defects can interact with each other in a way reminiscent of atoms bonding to form molecules. Each defect creates an atom-like mid-gap state within the band gap of the nanotube semiconductor. Two such defects, when brought close to each other, interact to form a split pair of orbitals akin to two hydrogen atoms covalently bonding to form a H2 molecule. This unexpected finding may help in understanding the nature of atomic defects in solids and provide a fresh perspective to the engineering of these color centers.
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