Photonic Dirac Nodal Line Semimetal

Our new paper titled “Double-bowl State in photonic Dirac nodal line semimetal” is published in Light: Science & Applications.

In this work we investigate a photonic Dirac nodal line semimetal (DNLS), which is not a trivial spinless extension of the electronic DNLS, and thus indicates the possibility of identifying new mechanisms unique for photonics to protect topological phases. We provide a stringent photonic realization of type-II DNLS with a ring shape four-fold band degeneracy. We measure the dispersion of the DNLS along relevant directions and thus provide the smoking gun for the realization of photonic DNLS. We deposit a silver film on top of this photonic DNLS and identify the double-bowl surface states possessed by this composite system through angle-resolved spectra.

Our system can serve as an ideal platform for investigating phenomena that require large field enhancement as well as manipulating light with an arbitrary polarization while studying polarization-sensitive light-matter interactions.

Fig. 1. Photonic Dirac nodal line semimetal. 

Fig. 2. Experimental observation of photonic Dirac nodal ring.

Fig. 3. Observation of the double-bowl states.

For full text:

https://doi.org/10.1038/s41377-021-00614-6

                                                                                                                                                                                                                            August 2021