Manipulation of transmission properties of a ladder-four-level Rydberg atomic system

Abstract

In this paper, we study the interaction of a giant ladder type four-level Rydberg atomic system with a weak light field and two strong control fields separately. We use the Monte Carlo method to calculate the dynamic evolution of this system and investigate the influence of dipole-dipole interaction on the transmission spectrum and second-order intensity correlation function of the weak probe field. By changing the value of detuning <inline-formula><tex-math id="M1">\begin{document}$\delta_e$\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M1.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M1.png"/></alternatives></inline-formula> and <inline-formula><tex-math id="M2">\begin{document}$\delta_r$\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M2.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M2.png"/></alternatives></inline-formula>, we can obtain the asymmetric transmission spectrum of the four-level Rydberg atomic system. The influence of Doppler effect on transmission spectrum and second-order intensity correlation function are also studied. By using super atom model, the influences of different incident probe field intensities on the transmission spectrum and the second-order intensity correlation function of probe field are discussed in the Rydberg atomic system. The results show that the transmission spectrum of the four-level Rydberg atomic system is symmetric when the detuning <inline-formula><tex-math id="M3">\begin{document}$\delta_e=\delta_r=0$\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M3.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M3.png"/></alternatives></inline-formula>. We obtain the asymmetric transmission spectrum of the system when the value of detuning <inline-formula><tex-math id="M4">\begin{document}$(\delta_e, \delta_r)$\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M4.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="11-20202077_M4.png"/></alternatives></inline-formula> changes from 0 to 43 MHz. In order to evaluate the influence of temperature on the transmission spectrum of the system, the Lorentz distribution function is introduced to calculate the polarizability analytically. And, the influence of temperature on the asymmetric transmission spectrum and the second-order intensity correlation function are discussed at finite temperature separately. The results show that the transmittance of the outgoing probe field at the transparent window decreases with the increase of the intensity of the incident probe light field under the condition of electromagnetically induced transparency. When the intensity of the incident probe field is constant, the asymmetric transmission spectrum can be obtained by changing the detuning of the strong field. In addition, when the propagation direction of the probe field is consistent with that of the strong field, the peak value of the transmission spectrum and the peak value of the second-order intensity correlation function of the system slightly increase as the temperature increases. When the propagation direction of the detection field is inconsistent with that of the strong field, the influence of the Doppler effect on the transmission spectrum and the second-order intensity correlation function of the system can be ignored.