https://doi.org/10.1140/epjp/s13360-022-02877-3
Regular Article
Controllable asymmetric diffraction grating with PT symmetry in quantum dot molecules
1
Department of Applied Physics, East China Jiaotong University, 330013, Nanchang, China
2
Department of Physics, Zhejiang Sci-Tech University, 310018, Hangzhou, China
Received:
22
September
2021
Accepted:
25
May
2022
Published online:
14
June
2022
A controllable and high-efficient asymmetric diffraction grating based on PT symmetry is proposed in multi-quantum dot molecular system. The proposed scheme utilizes the particle number modulation besides the modulation of the standing wave driving field. The interaction of the two modulations can change the parity of absorption and exhibits the striking PT symmetry, which is the key to realize the asymmetric diffraction grating. We observe that the positive and negative directions of the diffraction can be adjusted by changing the sign of the modulation amplitude or the sign of the detuning of the probe and driving fields. The increase in the interaction length can transfer the energy of the probe field to the high-order diffraction direction. By adjusting these parameters, high-efficiency diffraction can be achieved in the specified direction. Our scheme provides a feasible scheme for effectively controlling the diffraction direction and greatly improving the diffraction efficiency, which is beneficial to various applications of quantum information processing and large-angle all-optical splitter.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022
