Active research lines

Acoustic metamaterials and phononic crystals


Acoustic metamaterials are artificial structures that present new striking and exotic properties that are not present in conventional or natural materials. Using the concepts of strong dispersion and slow-sound, negative compressibility or negative mass density, these new materials can be designed to obtain interesting properties such as perfect sound absorption, zero-sound transmission, focusing or specific scattering patterns. In addition, the dynamics of high amplitude acoustic waves travelling through periodic structures show very special properties, e.g. anisotropic dispersion. A wide range of intrinsically nonlinear phenomena emerge due to the interaction between the nonlinearity and wave dispersion. I'm working in nonlinear localized waves in different media: cation lattices, layered acoustic media, sonic crystals and macroscopic lattices of oscillators.


Singular and vortex acoustic beams

High Order Bessel Beam

Currently I'm studying the acoustic field and acoustic radiation forces generated by high intensity focused ultrasound. High intensity focused ultrasound fields are characterized in the focal area by the appearance of nonlinear acoustic effects such as harmonic generation and self-(de)focusing. In addition, I'm studying vortex and nondiffracting acoustic beams, that can be generated under specific conditions. I'm interested in the generation of singular beams such as zero-th and higher order Bessel beams. These can be generated by using diffraction gratings in the same manner as Fresnel zone plate, and also by using acoustic metamaterials. Focusing of the beams is also considered and acoustic vortices can be easily generated by passive devices. Furthermore, nondiffracting nonlinear beams have been also obtained by using periodic materials under self-collimation regime.


Biomedical ultrasound applications

Ultrasound has important biomedical applications in both, therapy and imaging. I'm developing several biomedical ultrasound applications. First, I'm working in focused transcranial ultrasound devices based on metamaterials and protocols for the treatment of neurological disorders. Second, we develop several hybrid ultrasound imaging techniques for biomedical applications combining ultrasound with additional physical mechanisms to go a step beyond standard US imaging techniques. These include photoacoustic imaging, magneto-motive ultrasound and ultrasound elastography. Finally, we also develop ultrasonic technology to be applied to the field of odontology.


Simulations of acoustic and elastic waves in complex media

fdtd cell

I'm designing simulation techniques for acoustic fields in complex media. These computational methods include nonlinear acoustic propagation, arbitrary frequency dependent attenuation and dispersion for modelling biological media, as well as elastic waves in complex solid media. These time domain algorithms include arbitrary boundary conditions and media heterogeneity, and can be applied to biomedical ultrasound applications. On the other hand, I designed computational techniques for describe finite amplitude propagation through lattices and periodic media.


Industrial applications of ultrasound

Beyond the medical use of ultrasound, I'm developing together with Francisco Camarena's UMIL lab at I3M several industrial applications of ultrasound, mostly under agreement and contracts with private companies. These include industrial applications of ultrasound for food texture and quality characterization, and custom ultrasonic sensors and actuators for specific industrial applications. We are open to design, optimize and fabricate transducers on request for industrial applications.