High-order harmonic generation by carbon nanotubes density matrix approach

HIGH-ORDER HARMONIC GENERATION BY CARBON NANOTUBES DENSITY MATRIX APPROACH 

Institute for Nuclear Problems, Belarus State University Bobruiskaya 11, 220050 Minsk, Belarus E-mail maksim inp.minsk.by 

Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy Max-Born-Str. 2a, D-I2489 Berlin, Germany 

A rigorous quantum-mechanical description of the interaction of intense femtosecond laser pulses with single-wall carbon nanotubes has been presented. Quantum kinetic equations for the density matrix have been derived and solved numerically in the time domain. The influence of interband transitions on the high-order harmonics generation has been investigated. 

In the given paper we present a quantum-mechanical theory of HHG in CNs utilizing a single electron approximation in the tight-binding model. Our approach is based on the previous study HHG in CNs presented in Refs. [1,2] and allows us to incorporate into consideration direct interband transitions. We have calculated an axial current density, spectrum of which is responsible for HHG in CNs. 

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