Carbon nanotubes and graphene as terahertz emitters and detectors

• Main Authors: Portnoi, Mikhail E., Hartmann, Richard R., Kibis, O. V., Rosenau da Costa, M
• Format: text
• Published: Animo Repository 2012
• Subjects: Carbon nanotubes; Graphene; Submillimeter waves; Physics
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/7391
• Institution: De La Salle University

We propose and justify several proposals utilizing unique electronic properties of carbon nanotubes for a broad range of applications to terahertz (THz) optoelectronics, including THz generation by hot electrons in quasi-metallic nanotubes, frequency multiplication in chiral-nanotube-based superlattices controlled by a transverse electric field, and THz radiation detection and emission by armchair nanotubes in a strong magnetic field. Another direction of our research is THz applications of graphene. As a gapless semiconductor with ultra-high carrier mobility, graphene represents an ideal material for detecting THz radiation. We calculate absorption rates in graphene focusing on the effect of momentum alignment (anisotropy of the distribution function) of photoexcited carriers created by linearly polarized excitation. In conjunction with an extremely strong angular dependence of the tunneling probability for graphene p-n junctions optical alignment of momenta raises the possibility of using recently fabricated graphene p-n junction structures in polarization­sensitive THz detectors.