Light Fields Caused by Quantum Amplitude Decay

Hassan Kaatuzian, Ali Rostami, Ahmad Ajdarzadeh Oskouei

We extend the theory of quantum light memory in atomic ensemble of Lambda type atoms with considering lower levels coherency decay rate and one and two-photon detunings from resonances in low intensity and adiabatic passage limit. We obtain that with considering these parameters, group velocity of probe (information) pulse and its amplitude does not tend to zero by turning off the control field, therefore there is no complete storage of light. Also, we obtain that there will be a considerable decay of probe pulse and stored information. We calculate the minimum velocity and decay rate for probe (information) pulse. In addition, we obtain that in the Off-resonance case there will be a considerable distortion of the output light pulse that causes in loss of the stored information, then we present limitations for detunings and therefore for bandwidths of practical lasers also limitations for maximum storage time to have negligible distortion of stored information. We finally present the numerical calculations and compare them with analytical results.

H. C. Fan, Liyun Hu

Hassan Kaatuzian, Ali Rostami, Ahmad Ajdarzadeh Oskouei

We extend the theory of quantum light memory in atomic ensemble of Lambda type atoms with considering lower levels coherence decay rate and one and two-photon detunings from resonances in low intensity and adiabatic passage limit. We obtain that with considering these parameters, that there will be a considerable decay of probe pulse and stored information; also, we obtain that the group velocity of probe (light) pulse and its amplitude does not tend to zero by turning off the control field. We propose a method to keep the probe pulse in small values in turn off time of control field and to reduce the loss of the stored probe pulse. In addition, we obtain that in the Off-resonance case there will be a considerable distortion of the output light pulse that causes in loss of the stored information, then we present limitations for detunings and therefore for bandwidths of practical lasers also limitations for maximum storage time to have negligible distortion of stored information. We finally present the numerical calculations and compare them with analytical results.

Antonín Luk¿, Vlasta Peřinová

H. C. Fan, Liyun Hu

Indranil Bayal, Pradipta Panchadhyayee, Bibhas Kumar Dutta +1 more

Simultaneous interaction of two side-coupled waveguides with the dressed continuum represented by a linear waveguide array causes cross-coupling between the two evanescent decay-channels and results in the phenomenon of trapping of the light field in the spatial domain during propagation through the waveguide system. For specific parameter values, it has been shown that the trapping effect is possible for all relative positions of the waveguides side-coupled to the dressed continuum. The model also demonstrates non-exponential decay characteristics of the optical field amplitudes in the waveguides. Depending on the values of the propagation mismatch, the nonlinearity arising in the decay-rate characteristics exhibits features like optical Zeno and anti-Zeno effects.