Tunneling-induced large fifth-order nonlinearity with competing linear and nonlinear susceptibilities

摘要

Tunneling-induced large fifth-order nonlinearity is theoretically demonstrated in a double-quantum-dot system. The resonant tunneling induces constructive interference for the third- and fifth-order nonlinear effects. The competition between the linearity and nonlinearity leads to a transparency window at some frequency detunings, where the fifth-order nonlinear refractive index could be increased to be more than one order of magnitude larger than that on resonance. An analytical expression shows that the resonant tunneling mainly contributes to the dramatic enhancement of the fifth-order nonlinear response.