Influence of tunnelling-dependent cross-Kerr nonlinearity on photon drag using Sagnac interferometry

In a four-level quantum dot system connected with a Sagnac interferometer (Mach–Zehnder-type), photon drag (PD) under the influence of tunnelling-dependent cross-Kerr nonlinearity is explored. The PD, electric susceptibility, group index, group relativistic velocities are studied as functions of the tunnelling frequency. Additionally, in the presence of tunnelling-based Kerr effect in the system, improved positive group index and minimum group relativistic velocities are attained. Large drag angles are consequently observed in the system. The highest reached values for the group index are ng=1.60× 10^6 and 6× 10^6 . Likewise, the highest values for PD are reported as θ _d=± 0.080 , ± 0.112 and ± 0.120 radians. The outcomes shown here will advance quantum information, image coding/design, and rotation sensing technology.