The institute
FEMTO's news

You are here

First experimental observation of the roton effect in metamaterials

Experiments conducted jointly by FEMTO-ST and KIT demonstrate the control of forward and backward wave propagation by adjusting the frequency.

The roton is a quasi-particle that satisfies an unusual dispersion relation for acoustic waves in superfluid Helium-4 at low temperatures. Two recent theoretical papers have shown that roton-like dispersion relations exist in periodic media or metamaterials. Experimental demonstration of the effect was however still lacking. A joint study published in SciencesAdvances by the Karlsruher Institut für Technologie and FEMTO-ST reports on the experimental observation of the roton effect in elastic and acoustic metamaterials.

The following figure shows a 3D view of the acoustic metamaterial examined by the French group.

 

Remarkably, continuous tuning is obtained, by a simple adjustment of the wavelength, from forward wave propagation to backward wave propagation, followed by a minimum of the dispersion relation that marks the effective presence of the roton at audible frequencies.

The study illustrates that using higher-order interactions, that are relatively easy to implement with elastic and acoustic waves, opens unprecedented experimental possibilities for modeling the dispersion of phonons and their interactions.

This work was highlighted on the website of the French National Centre for Scientific Research : see the article

Contacts :

Vincent Laude

Muamer Kadic

  • Fei Gao wins the "Sustainable Future Visionary Award"

    Full professor at UTBM and researcher at FEMTO-ST institute, Fei Gao is today one of the world's leading specialists in fuel cells and digital twins.

    Read more
  • FEMTO-ST at MICRONORA trade fair 2022

    From September 27th to 30th, more than 600 direct exhibitors and 15000 professional visitors are expected in Besançon on the international microtechnology exhibition. FEMTO-ST and FEMTO Engineering will be present.

    Read more
  • The fastest pick-and-place robot in the world

    A research team has developed a miniature robot capable of manipulating micrometric objects at unprecedented speeds. This work has been published in the prestigious American journal "Science Robotics"

    Read more
  • Aude Bolopion receives the 2022 “Big-in-Small award”

    This yearly award, from the microrobotics international community in the MARSS conference in Toronto, promotes “the best microrobotician” of the year at the international level.

    Read more
  • FEMTO-ST : 2 full professors appointed to the IUF in its class 2022

    Ausrine MARGUERON-BARTASYTE and Daniel HISSEL are among the 164  national laureates appointed to the Institut Universitaire de France (IUF) by the Minister of Higher Education and Research

    Read more
  • Tribute to our colleague Philippe LUTZ

    Our scientific community of Burgundy-Franche-Comté has just suddenly lost Philippe LUTZ, full professor at the University of Franche-Comté and a leading figure in microrobotics and micromechatronics research at the FEMTO-ST laboratory.

    Read more
  • How to create a chemical bond with light?

    The formation of a chemical bond between two molecules often requires an activation process. Light is a stimulus that is particularly interesting

    Read more
  • Best student paper Award for Clément Carlé at the international conférence IFCS-EFTF2022

    This award was obtained in the "Microwave Frequency Standards" category of this major international conference in the field of time-frequency metrology, which took place in Paris from 24 to 28 April 2022.

    Read more
  • Daniel BRUNNER winner of an ERC Consolidator grant 2021

    Daniel BRUNNER is a CNRS researcher at the FEMTO-ST Institute and has been awarded a prestigious European Research Council Cosolidator Grant of 2M € for his INSPIRE project

    Read more
  • Daniel HISSEL awarded as « Fellow » of the IEEE society

    Professor in Electrical Engineering at the University of Franche-Comté and researcher at FEMTO-ST, Daniel Hissel has been awarded as  for his work on hydrogen systems.

    Read more

Pages