arXiv subjects

Zhihai Yao

Publications and source records attributed to Zhihai Yao.

5 recordsLinked to original sources

arXiv2021

Tunable photon blockade in a two-mode second-order nonlinear system embedded with a two-level atom

The conventional photon blockade for high-frequency mode is investigated in a two-mode second-order nonlinear system embedded with a two-level atom. By solving the master equation and calculating the zero-delay-time second-order correlation function $g^{(2)}(0)$, we obtain that strong photon antibunching can be achieved in this scheme. In particular, we find that by increasing the linear coupling coefficient of the system, a perfect blockade region will be formed near the zero second-order nonlinear coupling coefficient. Similarly, by increasing the nonlinear coupling coefficient of the system, the perfect blockade zone will appear. And this scheme is not sensitive to the reservoir temperature, both of which make the current system easier to implement experimentally.

quant-ph↗

arXiv2020

Unconventional photon blockade based on double second order nonlinear coupling system

In the recent publications [Phys. Rev. A 92,023838 (2015)], the unconventional photon blockade are studied in a two-mode-second-order-nonlinear system with nonlinear coupling between the low frequency and high frequency modes. In this paper, we study the unconventional photon blockade in a three-mode system with weakly coupled nonlinear cavities via $χ^{(2)}$ nonlinearity. By solving the master equation in the steady-state limit and calculating the zero-delay time second-order correlation function, we obtain the conditions of strong photon antibunching in the low frequency mode. The numerical result are compared with the analytical results, the results show that they are in complete agreement. By the analysis of numerical solutions, we find that this scheme is not sensitive to the change of decay rates and the reservoir temperature, and the three-mode drives make the system have more adjustable parameters, both of which increases the possibility of experimental implementation.

physics.optics↗

arXiv2020

Single-photon transport in one-dimensional coupled-resonator waveguide with second order nonlinearity coupling to a nanocavity containing a two-level atom and Kerr nonlinearity

We study controllable single photon scattering in a one-dimensional waveguide coupling with an additional cavity by second order nonlinear materials in a non-cascading configuration, where the additional cavity is embedded with two-level atom and filled with Kerr-nonlinear materials. Considering the second order nonlinear coupling, we analyze the transmission properties of the three different coupling forms as follows: (i) The two-level atom is excited without the Kerr-nonlinearity. (ii)The Kerr-nonlinearity is excited without the two-level atom. (iii) Both of the two-level atom and Kerr-nonlinearity are excited. The transmission and reflection amplitudes are obtained by the discrete coordinates approach for the three cases. The results showed that the transmission properties can be adjusted by the above three different coupling forms, which indicate our scheme can be used as a single photon switch to control the transmission and reflection of the single photon in the one-dimensional coupled resonant waveguide. We compared the results with [Phys. Rev. A 85, 053840(2012)] and find the advantages.

physics.optics↗

arXiv2020

Kerr-nonlinearity Enhanced Conventional Photon Blockade in Second-order-nonlinear System

In the recent publication [Phys. Rev. B 87, 235319 (2013)], the conventional photon blockade(CPB) was studied for the low frequency mode in a second-order nonlinear system. In this paper, we will study the CPB for the high frequency mode in a second-order nonlinear system with the Kerr nonlinearity filling in the low-frequency cavity. By solving the master equation and calculating the zero-delay-time second order correlation function $g^{(2)}(0)$, strong photon antibunching can be obtained in the high frequency cavity. The optimal condition for strong antibunching is found by analyticcal culations and discussions of the optimal condition are presented. We find that the Kerr-nonlinearities can enhanced the CPB effect. In addition, this scheme is not sensitive to the reservoir temperature, which make the current system easier to implement experimentally.

physics.optics↗

arXiv2018

Ghost imaging for an occluded object

Imaging for an occluded object is usually a difficult problem, in this letter, we introduce an imaging scheme based on computational ghost imaging, which can obtain the image of a target object behind an obstacle. According to our theoretical analysis, once the distance between the object and the obstacle is far enough, one can obtain the image of the object by using ghost imaging technique. The wavelength of the light source also affects the quality of the reconstructed image. In addition, if the bucket detector is placed far away from the obstacle, a tiny point-like detector without collecting lens can be applied to realize the imaging. These theoretical results above have been verified with our numerical simulations. Furthermore, the robustness of this imaging scheme is also investigated.

physics.optics↗