Giant Two-photon Absorption in Circular Graphene Quantum Dots in Infrared Region

نویسندگان

  • Xiaobo Feng
  • Zhisong Li
  • Xin Li
  • Yingkai Liu
چکیده

We investigate theoretically the two-photon absorption (TPA) for circular graphene quantum dots (GQDs) with the edge of armchair and zigzag on the basis of electronic energy states obtained by solving the Dirac-Weyl equation numerically under finite difference method. The expressions for TPA cross section are derived and the transition selection rules are obtained. Results reveal that the TPA is significantly greater in GQDs than conventional semiconductor QDs in infrared spectrum (2-6 um) with a resonant TPA cross section of up to 10(11 )GM. The TPA peaks are tuned by the GQDs' size, edge and electron relaxation rate.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Two-Photon Fluorescence in N-Doped Graphene Quantum Dots

Nitrogen-doped graphene quantum dots (N-GQDs) were fabricated by microwave-assisted hydrothermal technique. The optical properties of the N-GQDs were studied. The luminescence of the N-GQDs can be tuned by varying the excitation wavelength. Furthermore, two-photon luminescence of the N-GQDs excited by near-infrared laser can be obtained. It is shown that N-doping play a key role on two-photon l...

متن کامل

High temperature acidic oxidation of multiwalled Carbon nanotubes and synthesis of Graphene quantum dots

The acid oxidation of carbon nanotube generally results in opening the close ends of the nanotube and to make surface modifications. Herewith, Multiwall carbon nanotubes (MWCNTs) were oxidized in acids at high temperature experimental conditions which led to the formation of graphene quantum dots (GQDs).   High resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectro...

متن کامل

Two-photon-enhanced three-photon absorption in transition-metal-doped semiconductor quantum dots

We report the observation of two-photon-enhanced three-photon absorption (3PA) in transition-metal-doped semiconductor quantum dots (d-QDs) in the near-infrared spectral region. Due to the degeneracy between two-photon transitions to the states of metal ions inside the bandgap and three-photon transitions to the excitonic state, the 3PA cross-section is greatly enhanced in comparison with the p...

متن کامل

High temperature acidic oxidation of multiwalled Carbon nanotubes and synthesis of Graphene quantum dots

The acid oxidation of carbon nanotube generally results in opening the close ends of the nanotube and to make surface modifications. Herewith, Multiwall carbon nanotubes (MWCNTs) were oxidized in acids at high temperature experimental conditions which led to the formation of graphene quantum dots (GQDs).   High resolution transmission electron microscope (HRTEM), energy dispersive X-ray spectro...

متن کامل

Strong Two - Photon - Induced Fluorescence from Photostable , 2 Biocompatible Nitrogen - Doped Graphene Quantum Dots for Cellular 3 and Deep - Tissue Imaging

7 ABSTRACT: Bright two-photon fluorescent probes are highly 8 desirable to be able to optically probe biological activities deep 9 inside living organisms with larger imaging depth, minor 10 autofluorescence background, and less photodamage. In this 11 study, we report the biocompatible nitrogen-doped graphene 12 quantum dots (N-GQDs) as efficient two-photon fluorescent 13 probes for cellular a...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 6  شماره 

صفحات  -

تاریخ انتشار 2016