The European Commission considers our efforts a success story! Many thanks for this! More importantly, many thanks to our PhDs and Postdocs!
Here is the story, link: ec.europa.eu.
I always wanted to have something equivalent to an acoustic laser at hand. Lasing or gain medium for sound waves? Yes, this is exciting. Topics in optical metamaterials are entirely dedicated to that, like “loss-compensated metamaterials” or “active plasmonics”, let alone “laser physics”!! My old friend Ying had this fantastic idea of using thermoacoustics to generate sound in conductors when an AC current is properly applied. Yes, we would not generate quanta of sound, like photons, but it would be a neat way to incorporate this effect in lattices to explore topological lasers…sorry, I mean, topological sasers! “S” is for sound my friends! Ying suggested using carbon nanotube films as they have already shown in the past to be efficient sound generators. I don’t have to explain the effort (time and money) behind the construction that consisted in coating really many crystal rods by those CNT films. Each coated rod needed electrical leads, a connection to a circuit, and all arranged in a honeycomb lattice! A truly active acoustic graphene-like material! Now that you are here, you have probably heard of a band gap. With the right geometrical arrangement you can make it topological non-trivial, but in its active construction, the resulting edge states appear with enhanced amplitude. To my amazement, we were able to out-couple those guys into highly collimated, and topologically protected acoustic SASER beams! I hope you enjoy reading the paper!
Nature 597, 655 (2021).
Link to the paper: https://doi.org/10.1038/s41586-021-03833-4
Summary published in Science & Vie (monthly science magazine published in France).
Here is the acoustic answer to a Faraday cage – excited to have this published in Phys. Rev. Lett. as an editors’ choice with Yun Lai and Nick Fang!
We found the acoustic analogy of the Förster resonance energy transfer between donors and acceptors! After a hard fought battle (rejected in PRL and AFM) the paper will soon appear in Nat. Comm. Image taken from: DOI:10.3390/ijms131114929
Today we published a News and Views in Nature Nanotechnology where we discuss how topological defects using a man-made vortex can trap either light or sound!
Nature’s Communications Physics journal has been around not even two years, and it’s first review article, yes, our Topological sound contribution is the second highest cited paper of this journal! 💪
