Strain Dependent Electronic Structure and Optical Response of Carbon Nanotube

Abstract

One dimensional quasi-particles for low dimensional systems there is less surrounding material than in bulk systems, leading to weak dielectric screening of the electron-electron and electron-hole interaction. As a consequence quasi particle shifts are as large and excitonic effects were found strong. In order to produce strain sensing based on carbon nanotubes electronic and optical properties as well as strain dependence, so it is essential for the development of micro opto-electro mechanical systems, such as strain tunable emitters based on carbon nanotubes or tunable optical sensors. We have used first principles for electronic structure calculations based on G. W. approximation and Bethe-Salpeter equation to obtain strong strain related shifts in the optical absorption spectrum of carbon nanotube. We have found that exciton binding energy in strained carbon nanotubes is a function of the band gap and study leaded to strain dependent inhomogeneous dielectric screening. This presented that deformation potentials of electronic eigen-values and exciton binding energies were considered for the solution of strain dependent optical spectra of carbon nanotubes. The scaling relation allowed to extrapolate the shift of optical transition from the unstrained to the strained state based on the strain induced shift of electronic energy levels.