Tunneling-induced π-phase shift with a single-photon signal field in asymmetric double quantum wells

J. H. Li, Rong Yu, Chunling Ding +1 more

Leonardo Silvestri, F. Bassani, G. Czajkowski +1 more

Xiangying Hao, J. H. Li, Xin‐You Lü +1 more

Hongju Guo, Lichun Wang, Yueping Niu +2 more

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 π-phase shift at a single-photon level which is favorable for the applications in two-qubit quantum logic gates.

G. J. Papadopoulos, P. Melas

Hui Sun, Shuangli Fan, Xun‐Li Feng +4 more

We propose an asymmetric quantum well structure to realize strong interaction between two slow optical pulses. The essential idea is the combination of the advantages of inverted-Y type scheme and resonant tunneling. We analytically demonstrate that giant cross-Kerr nonlinearity can be achieved with vanishing absorptions. Owing to resonant tunneling, the contributions of the probe and signal cross-Kerr nonlinearities to total nonlinear phase shift vary from destructive to constrictive, leading to nonlinear phase shift on order of π at low light level. In this structure, the scheme is inherent symmetric for the probe and signal pulses. Consequently, the condition of group velocity matching can be fulfilled with appropriate initial electron distribution.