title: Controllable entanglement and polarization phase gate in coupled double quantum-well structures.
abstract: By analyzing the nonlinear optical response in an asymmetric coupled double quantum well structure based on the intersubband transitions, we show that a giant Kerr nonlinearity with a relatively large cross-phase modulation coefficient can be used to produce efficient photonphoton entanglement and implement an all-optical two-qubit quantum polarization phase gate. We also demonstrate that such photon-photon entanglement is practically controllable and may facilitate more practical applications in all-optical quantum information and computation.
authors.affiliation: Institute of Photonics Technologies, National Tsing-Hua University, Hsinchu 300, Taiwan.
authors.forename: Wen-Xing
authors.initials: WX
authors.lastname: Yang
authors.forename: Ray-Kuang
authors.initials: RK
authors.lastname: Lee