Structure-dependent hydrostatic deformation potentials of individual single-walled carbon nanotubes

The hydrostatic pressure coefficients of interband transition energies of a number of single-walled carbon nanotubes with different chiralities were measured. Optical experiments were performed on debundled, single-walled carbon nanotube suspensions with hydrostatic pressure applied by diamond anvil cells. The pressure coefficients of the band-gap energies are negative and dependent on the nanotube structure, while the second van Hove transitions are much less sensitive to hydrostatic pressure. An empirical equation that relates the pressure coefficients to nanotube structure is presented and discussed.