Two Independent Synthetic Dimensions Constructed in Single Optical Cavity

On January 2^nd, 2020, Prof. Shanhui Fan from Stanford University (SGY 88) and Research Fellow Luqi Yuan from Shanghai Jiao Tong University, as the co-corresponding authors, published a paper entitled "A single photonic cavity with two independent physical synthetic dimensions" in Science.

Synthetic dimensions have attracted broad attention because of its ability to provide a multifunctional platform for the realization of efficient gauge field and topological physics. Synthetic photonic dimensions, which involves constructing synthetic dimensions utilizing the frequency freedom of light, is a novel and booming research field [1]. It has shown its great potential since it has been put forward, and has been validated experimentally [2]. The construction of a two-dimensional artificial synthetic space in a single optical cavity (zero dimension) is also theoretically demonstrated [3].

In this research, the researchers built two independent synthetic dimensions in a single optical cavity for the first time. Important physical phenomena corresponding to Hall ladder lattices, such as effective magnetic gauge potential and topological chiral one-way edge current, have also been observed in the experiments in this two-dimensional synthesis space.

Observation of the unidirectional boundary flow of the light field related to the synthesized Hall ladder lattice

This work has experimentally proved that high dimensional and complex physical effects can be realized and studied in a simple optical system by constructing multiple synthetic dimensions, thus greatly enriching the application prospect of the concept of synthetic dimensions. At the same time, these physical effects can also be used to explore the possibility of manipulating various light fields. In simple words, the concept of multiple synthetic dimensions can be used to study higher-dimensional physics in simple systems.

The project was supported by the general project of the Natural Science Foundation of China (11974245).

Paper link:

https://science.sciencemag.org/content/early/2019/11/25/science.aaz3071

Reference:

[1] L. Yuan, Q. Lin, M. Xiao, and S. Fan, “Synthetic dimension in photonics,” Optica 5, 1396 (2018).

[2] A. Dutt, M. Minkov, Q. Lin, L. Yuan, D. A. B. Miller, and S. Fan, “Experimental band structure spectroscopy along a synthetic dimension,” Nat. Commun. 10, 3122 (2019).

[3] L. Yuan, Q. Lin, A. Zhang, M. Xiao, X. Chen, and S. Fan, “Photonic gauge potential in one cavity with synthetic frequency and orbital angular momentum dimensions,” Phys. Rev. Lett. 122, 083903 (2019).