A theoretical investigation is carried out into the cross phase modulation (XPM) in an asymmetric double AlGaAs/GaAs quantum wells structure with a common continuum. It is found that, combining resonant tunneling-induced transparency and constructive interference in the third-order Kerr effect, a giant XPM can be achieved with vanishing linear and nonlinear absorptions, accompanied by the velocities of the probe and signal fields being matched. Furthermore, this giant XPM could induce a \pi-phase shift at a single-photon level which is favorable for the applications in two-qubit quantum logic gates.
© 2009 Chinese Optics Letters
(190.3270) Nonlinear optics : Kerr effect
(190.4400) Nonlinear optics : Nonlinear optics, materials
(270.1670) Quantum optics : Coherent optical effects
(270.5585) Quantum optics : Quantum information and processing
Hongju Guo, Lichun Wang, Yueping Niu, Shiqi Jin, and Shangqing Gong, "Tunneling-induced π-phase shift with a single-photon signal field in asymmetric double quantum wells," Chin. Opt. Lett. 7, 886-890 (2009)