Welcome to the web page of: IEMN / AIMAN Research Group & LEMAC*
*LEMAC is the Joint European Laboratory on nonlinear magneto-acoustics of condensed matter
• Research area : « Nonlinear Magnetoacoustics of condensed matter »
General aim of the work:
Nonlinear Magnetoacoustics of condensed matter is an original field which focuses on the dynamical interactions between the magnetic and elastic subsystems of specific active materials. These couplings provide totally new and unexpected phenomena in the fields of solid state physics, nonlinear dynamics and acoustics, and stimulate innovative concepts in the fields of ultrasonic systems, microsystems and functional electronics.
Organisation of the research activity:
It is built around four main interconnected themes, each of them corresponding to a self-consistent part of activity with some fundamental and original approaches where the LEMAC (and AIMAN group) has a leadership position and bring clear added value on the international scene.
1) Fundamental Magneto-Acoustics :
The fundamental magneto-acoustics bloc is the theme where the new theoretical concepts are elaborated and investigated experimentally. This block delivers the main inputs to the other research themes.
1.1) Studies of parametric interactions of pairs of conjugate phonons
1.2) Explosive dynamics and localization of wave triads in a coupled magnetoelastic system
2) Active Materials and Nanostructures :
To bring to applications these new concepts, some active magnetic materials are necessary either in bulk, film or nanostructured forms. The elaboration, investigation, and tailoring of such materials specifically dedicated to magneto-acoustics form the second central block.
2.1) Active ferrite magneto-ceramics with homogeneous or gradient distribution of porosities
2.2) Artificial multiferroic nanostructures with induced critical states
2.3) Magneto-acoustic nanoparticles dedicated to diagnostic or therapy using MAWPC
3) Magneto-Acoustic Wave Phase Conjugation (MAWPC) :
Based on bulk magneto-acoustic ceramics, magneto-acoustic phase conjugation is an original way to realize ultrasonic wave fronts reversal with giant coherent amplification. The main applications are nonlinear ultrasonic Imaging, ultrasonic characterization and flow velocimetry.
3.1) NL imaging and characterization of complex and moving media
3.2) MAWPC for ultrasonic investigations without contacts and velocity characterization of air flows
3.3) High frequency MAWPC system for microfluidic MEMS characterization
3.4) MAWPC and magneto-acoustic nanoparticles for diagnostic and therapy
4) Micro-Magneto-Electro-Mechanical Systems (MMEMS) :
The goal here is the elaboration of innovative Microsystems based on magnetic nanostructures with giant magnetostriction and induced critical states, or related multiferroic nanostructures. The resulting microdevices are called : Micro-Magneto-Electro-Mechanical-Systems (MMEMS).
4.1) Integrated MMEMS based on magnetic and related multiferroic nanostructures with artificially induced critical states.
4.2) Integrated MMMS based on magneto-dynamic effect
- Arrays of microvalves for active flow control.
- Hightly integrated matrix of micro-actuators for tactile interfaces
- Soft reconfigurable RF antennas.
