Impurity effects in boron-nitride heteropolar nanotubes
نویسنده
چکیده
Impurity scattering properties for optical excitations in boron-nitride (BN) heteropolar nanotubes are investigated theoretically. We extend the continuum k · p model of the carbon nanotubes to that of the BN systems, where site energies are introduced at the boron and nitrogen atoms in order to take account of the strong ionic properties of the BN bonds. We show that the backward scattering components of the t matrix are small with the order a/L, a being the lattice constant and L the circumference length. Therefore, the BN nanotubes are good conductors for photoexcitations. E-mail address: [email protected]; URL: http://staff.aist.go.jp/k.harigaya/ Corresponding address
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