TITLE:
FDTD Simulation of Three Photon Absorption and Realization of NAND Gate with GaAs Wire Waveguide
AUTHORS:
Ivy Dutta, Anirban Roy Chowdhury, Dharmadas Kumbhakar
KEYWORDS:
Three Photon Absorption; Fifth Order Nonlinearity; FDTD; Full Vector Finite Difference Method; Pump Beam and Probe Beam
JOURNAL NAME:
Optics and Photonics Journal,
Vol.3 No.5,
August
26,
2013
ABSTRACT: GaAs has high three photon absorption (3PA) co-efficient
at mid-infrared wavelength like2.2mm and waveguides can be formed with this material like silicon
nano-wires. It is shown that three-photon-absorption in GaAs wire waveguide can
be utilized to form NAND gate. Three-photon-absorption is incorporated in
one-dimensional Finite Difference Time Domain (FDTD) equations. The
evolution of a probe pulse under the influence of a pump pulse through crossabsorption
in a waveguide is investigated using FDTD simulation, where the dominant
process is nonlinear three-photon-absorption. Output probe power dependence on
input pump power shows that GaAs waveguide NAND gate has higher extinction
ratio in comparison to NAND gate using two-photon-absorption in silicon
waveguide.