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Ultra-high frequency vortex-based tweezers for microparticles manipulation with high spatial selectivity and nanoNewton forces
Authors:
Roudy Al Sahely,
J-C Gerbedoen,
Nikolay Smagin,
Ravinder Chutani,
Olivier Bou Matar,
Michael Baudoin
Abstract:
Acoustical tweezers based on focused acoustical vortices open some tremendous perspectives for the in vitro and in vivo remote manipulation of millimetric down to micrometric objects, with combined selectivity and applied forces out of reach with any other contactless manipulation technique. Yet, the synthesis of ultra-high frequency acoustical vortices to manipulate precisely micrometric objects…
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Acoustical tweezers based on focused acoustical vortices open some tremendous perspectives for the in vitro and in vivo remote manipulation of millimetric down to micrometric objects, with combined selectivity and applied forces out of reach with any other contactless manipulation technique. Yet, the synthesis of ultra-high frequency acoustical vortices to manipulate precisely micrometric objects remains a major challenge. In this paper, the synthesis of a 250 MHz acoustical vortex is achieved with an active holographic source based on spiraling interdigitated transducers. It is shown that this ultra-high frequency vortex enables to trap and position individual particles in a standard microscopy environment with high spatial selectivity and nanoNewton forces. This work opens perspectives to explore acoustic force spectroscopy in some force ranges that were not accessible before.
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Submitted 10 March, 2022;
originally announced March 2022.
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Giant magnetoelastic coupling in Love acoustic waveguide based on uniaxial multilayered TbCo2/FeCo nanostructured thin film on Quartz ST-cut
Authors:
Aurelien Mazzamurro,
Yannick Dusch,
Philippe Pernod,
Olivier Bou Matar,
Ahmed Addad,
Abdelkrim Talbi,
Nicolas Tiercelin
Abstract:
Coupling between dynamic strain and magnetization in ferromagnetic thin films has attracted special consideration as it presents both intriguing fundamental physics problems and technological importance for potential multi-functional devices and information handling. The dynamic strain can be generated by acoustic waves including bulk, surface or guided waves. In this work, we propose the theoreti…
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Coupling between dynamic strain and magnetization in ferromagnetic thin films has attracted special consideration as it presents both intriguing fundamental physics problems and technological importance for potential multi-functional devices and information handling. The dynamic strain can be generated by acoustic waves including bulk, surface or guided waves. In this work, we propose the theoretical and experimental investigation of the interaction of pure shear horizontal (SH) wave with a uniaxial multilayered TbCo2/FeCo thin film in a delay line configuration fabricated on Quartz ST-90X cut. We evaluate theoretically the evolution of phase velocity as a function of magnetic field and experimentally the variation of the transmission coefficient. A piezomagnetic model was developed allowing us to calculate the elastic stiffness constants of the multilayer as a function of the applied magnetic field. The model was also implemented for acoustic waves dispersion curves calculation. We show that the evolution of phase velocity is dominated by the C66 elastic stiffness constant variation as expected for the case of shear horizontal surface wave. The fabricated device let us exciting both fundamental and third harmonic shear mode at 410 MHz and 1.2 GHz, respectively. For both modes, the theoretical results corroborate very well the experimental ones. At 1.2 GHz the mode exhibits a maximum phase velocity shift close to 2.5% and an attenuation reaching 500 dB/cm, for a sensitivity as high as 250 ppm/Oe. The reported theoretical model and experimental results are of tremendous interest for the development of advanced devices for magnetic field sensing applications as well as investigating magnon-phonon interaction at a fundamental level.
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Submitted 22 January, 2020; v1 submitted 2 August, 2019;
originally announced August 2019.
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Autler-Townes splitting and acoustically induced transparency based on Love waves interacting with pillared meta-surface
Authors:
Yuxin Liu,
Abdelkrim Talbi,
El Houssaine El Boudouti,
Olivier Bou Matar,
Philippe Pernod,
Bahram Djafari-Rouhani
Abstract:
Autler-Townes Splitting (ATS) and Electromagnetically Induced Transparency (EIT) are similar phenomena but distinct in nature. They have been widely discussed and distinguished by employing the Akaike information criterion (AIC). However, such work is lacking in acoustic system. In this work, the interaction of Love waves with two-line pillared meta-surface is numerically investigated by Finite El…
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Autler-Townes Splitting (ATS) and Electromagnetically Induced Transparency (EIT) are similar phenomena but distinct in nature. They have been widely discussed and distinguished by employing the Akaike information criterion (AIC). However, such work is lacking in acoustic system. In this work, the interaction of Love waves with two-line pillared meta-surface is numerically investigated by Finite Element Method. Acoustic analogue of ATS, Fabry-Perot resonance and cavity modes are first demonstrated in two lines of identical pillars by varying the distance between the pillar lines. By detuning the radius of one line of pillars, Fabry-Perot resonance along with two different pillar resonances give rise to the acoustic analogue of EIT (AIT) when the distance between the pillar lines is a multiple of half wavelength. ATS and AIT formula models are used to fit the transmission spectra, showing good agreements with numerical results. The quality of the fit models is quantitatively evaluated by resorting to the AIC. We show that theoretical and analytical discrimination between ATS and AIT are methodologically complementary. These results should have important consequences for potential acoustic applications such as wave control, designing of meta-materials and bio-sensors.
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Submitted 29 May, 2019; v1 submitted 11 March, 2019;
originally announced March 2019.
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Interaction of Love waves with coupled cavity modes in a 2D holey phononic crystal
Authors:
Yuxin Liu,
Abdelkrim Talbi,
Bahram Djafari-Rouhani,
El Houssaine El Boudouti,
Lucie Drbohlavova,
Vincent Mortet,
Olivier Bou Matar,
Philippe Pernod
Abstract:
The interaction of Love waves with square array of pillars deposited on a cavity defined in a 2D holey phononic crystal is numerically investigated using Finite Element Method. First, the existence of SH surface modes is demonstrated separately for phononic crystals that consist of square arrayed holes, or rectangular arrayed Ni pillars, respectively in, or on, a SiO2 film deposited on a ST-cut qu…
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The interaction of Love waves with square array of pillars deposited on a cavity defined in a 2D holey phononic crystal is numerically investigated using Finite Element Method. First, the existence of SH surface modes is demonstrated separately for phononic crystals that consist of square arrayed holes, or rectangular arrayed Ni pillars, respectively in, or on, a SiO2 film deposited on a ST-cut quartz substrate. The coupling between SH modes and torsional mode in pillars induces a transmission dip that occurs at a frequency located in the range of the band-gap of the holey phononic crystal. Second, a cavity is constructed by removing lines of holes in the holey phononic crystal and results in a transmission peak that matches the dip. The optimal geometrical parameters enable us to create a coupling of the cavity mode and the localized pillar mode by introducing lines of pillars into the cavity, which significantly improved the efficiency of the cavity without increasing the crystal size. The obtained results will pave the way to implement advanced designs of high-performance electroacoustic sensors based on coupling modes in phononic crystals.
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Submitted 2 March, 2019; v1 submitted 9 November, 2018;
originally announced November 2018.
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Influence of viscosity on acoustic streaming in sessile droplets: an experimental and a numerical study with a Streaming Source Spatial Filtering (SSSF) method
Authors:
Antoine Riaud,
Michael Baudoin,
Oliver Bou Matar,
Jean-Louis Thomas,
Philippe Brunet
Abstract:
When an acoustic wave travels in a lossy medium such as a liquid, it progressively transfers its pseudo-momentum to the fluid, which results in a steady acoustic streaming. Remarkably, the phenomenon involves a balance between sound attenuation and shear, such that viscosity vanishes in the final expression of the velocity field. For this reason, the effect of viscosity has long been ignored in ac…
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When an acoustic wave travels in a lossy medium such as a liquid, it progressively transfers its pseudo-momentum to the fluid, which results in a steady acoustic streaming. Remarkably, the phenomenon involves a balance between sound attenuation and shear, such that viscosity vanishes in the final expression of the velocity field. For this reason, the effect of viscosity has long been ignored in acoustic streaming experiments. Here, we show experimentally that the viscosity plays a major role in cavities such as the streaming induced by surface acoustic waves in sessile droplets. We develop a numerical model based on the spatial filtering of the streaming source term to compute the induced flow motion with dramatically reduced computational requirements. We evidence that acoustic fields in droplets are a superposition of a chaotic field and a few powerful caustics. It appears that the caustics drive the flow, which allows a qualitative prediction of the flow structure. Finally, we reduce the problem to two dimensionless numbers related to the surface and bulk waves attenuation and simulate hemispherical sessile droplets resting on a lithium niobate substrate for a range of parameters. Even in such a baseline configuration, we observe at least four distinct flow regimes. For each of them, we establish a correlation of the average streaming speed in the droplet, which is increasingly dependent on the bulk wave attenuation as the viscosity increases. These correlations extend our results to a wide range of fluids and actuation frequencies.
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Submitted 12 May, 2016;
originally announced May 2016.
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Dynamics of sessile and pendant drop excited by surface acoustic waves: gravity effects and correlation between oscillatory and translational motions
Authors:
Adrien Bussonière,
Michael Baudoin,
Philippe Brunet,
Olivier Bou Matar
Abstract:
When sessile droplets are excited by ultrasonic traveling surface acoustic waves (SAWs), they undergo complex dynamics with both oscillations and translational motion. While the nature of the Rayleigh-Lamb quadrupolar drop oscillations has been identified, their origin and their influence on the drop mobility remains unexplained. Indeed the physics behind this peculiar dynamics is complex with non…
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When sessile droplets are excited by ultrasonic traveling surface acoustic waves (SAWs), they undergo complex dynamics with both oscillations and translational motion. While the nature of the Rayleigh-Lamb quadrupolar drop oscillations has been identified, their origin and their influence on the drop mobility remains unexplained. Indeed the physics behind this peculiar dynamics is complex with nonlinearities involved both at the excitation level (acoustic streaming and radiation pressure) and in the droplet response (nonlinear oscillations and contact line dynamics). In this paper, we investigate the dynamics of sessile and pendant drops excited by SAWs. For pendant drops, so-far unreported dynamics are observed close to the drop detachment threshold with the suppression of the translational motion. Away from this threshold, the comparison between pendant and sessile drop dynamics allows us to identify the role played by gravity or more generally by an initial or dynamically induced stretching of the drop. In turn, we elucidate the origin of the resonance frequency shift, as well as the origin of the strong correlation between oscillatory and translational motion. We show that for sessile drops, the velocity is mainly determined by the amplitude of oscillation and that the saturation observed is due to the nonlinear dependence of the drop response frequency on the dynamically induced stretching.
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Submitted 15 January, 2016;
originally announced January 2016.
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SAW synthesis with IDTs array and the inverse filter: toward a versatile SAW toolbox for microfluidics and biological applications
Authors:
Antoine Riaud,
Michael Baudoin,
Jean-Louis Thomas,
Olivier Bou Matar
Abstract:
Surface acoustic waves (SAWs) are versatile tools to manipulate fluids at small scales for microfluidics and bio- logical applications. A non-exhaustive list of operations that can be performed with SAW includes sessile droplet displacement, atomization, division and merging but also the actuation of fluids embedded in microchannels or the manipulation of suspended particles. However, each of thes…
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Surface acoustic waves (SAWs) are versatile tools to manipulate fluids at small scales for microfluidics and bio- logical applications. A non-exhaustive list of operations that can be performed with SAW includes sessile droplet displacement, atomization, division and merging but also the actuation of fluids embedded in microchannels or the manipulation of suspended particles. However, each of these operations requires a specific design of the wave generation system, the so-called interdigitated transducers (IDTs). Depending on the application, it might indeed be necessary to generate focused or plane, propagating or standing, aligned or shifted waves. Furthermore, the possibilities offered by more complex wave-fields such as acoustical vortices for particle tweezing and liquid twisting cannot be explored with classical IDTs. In this paper, we show that the inverse filter technique coupled with an interdigitated transducers array (IDTA) enables to synthesize all classical wave-fields used in microfluidics and biological applications with a single multi- function platform. It also enables to generate swirling SAWs, whose potential for the on-chip synthesis of tailored acoustical vortices has been demonstrated lately. The possibilities offered by this platform is illustrated by performing successively many operations on sessile droplets with the same system.
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Submitted 15 January, 2016;
originally announced January 2016.
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Taming the degeneration of Bessel beams at anisotropic-isotropic interface: toward 3D control of confined vortical waves
Authors:
Antoine Riaud,
Jean-Louis Thomas,
Michael Baudoin,
Olivier Bou Matar
Abstract:
Despite their self-reconstruction properties in heterogeneous media, Bessel beams are known to degenerate when they are refracted from an isotropic to an anisotropic medium. In this paper, we study the converse situation wherein an anisotropic Bessel beam is refracted into an isotropic medium. It is shown that these anisotropic Bessel beams also degenerate, leading to confined vortical waves that…
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Despite their self-reconstruction properties in heterogeneous media, Bessel beams are known to degenerate when they are refracted from an isotropic to an anisotropic medium. In this paper, we study the converse situation wherein an anisotropic Bessel beam is refracted into an isotropic medium. It is shown that these anisotropic Bessel beams also degenerate, leading to confined vortical waves that may serve as localized particle trap for acoustical tweezers. The linear nature of this degeneration allows the 3D control of this trap position by wavefront correction. Theory is confronted to experiments performed in the field of acoustics. A swirling surface acoustic wave is synthesized at the surface of a piezoelectric crystal by a MEMS integrated system and radiated inside a miniature liquid vessel. The wavefront correction is operated with inverse filter technique. This work opens perspectives for contactless on-chip manipulation devices.
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Submitted 31 August, 2015;
originally announced August 2015.
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Synthesis of anisotropic swirling surface acoustic waves by inverse filter, towards integrated generators of acoustical vortices
Authors:
Antoine Riaud,
Jean-Louis Thomas,
Eric Charron,
Adrien Bussonnière,
Olivier Bou Matar,
Michaël Baudoin
Abstract:
From radio-electronics signal analysis to biological samples actuation, surface acoustic waves (SAW) are involved in a multitude of modern devices. Despite this versatility, SAW transducers developed up to date only authorize the synthesis of the most simple standing or progressive waves such as plane and focused waves. In particular, acoustical integrated sources able to generate acoustical vorti…
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From radio-electronics signal analysis to biological samples actuation, surface acoustic waves (SAW) are involved in a multitude of modern devices. Despite this versatility, SAW transducers developed up to date only authorize the synthesis of the most simple standing or progressive waves such as plane and focused waves. In particular, acoustical integrated sources able to generate acoustical vortices (the analogue of optical vortices) are missing. In this work, we propose a flexible tool based on inverse filter technique and arrays of SAW transducers enabling the synthesis of prescribed complex wave patterns at the surface of anisotropic media. The potential of this setup is illustrated by the synthesis of a 2D analog of 3D acoustical vortices, namely "swirling surface acoustic waves". Similarly to their 3D counterpart, they appear as concentric structures of bright rings with a phase singularity in their center resulting in a central dark spot. Swirling SAW can be useful in fragile sensors whose neighborhood needs vigorous actuation, and may also serve as integrated transducers for acoustical vortices. Since these waves are essential to fine acoustical tweezing, swirling SAW may become the cornerstone of future micrometric devices for contactless manipulation.
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Submitted 28 April, 2015; v1 submitted 26 April, 2015;
originally announced April 2015.
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Cyclones and attractive streaming generated by acoustical vortices
Authors:
Antoine Riaud,
Michael Baudoin,
Jean-Louis Thomas,
Olivier Bou Matar
Abstract:
Acoustical and optical vortices have attracted large interest due to their ability in capturing and manipulating particles with the use of the radiation pressure. Here we show that acoustical vortices can also induce axial vortical flow reminiscent of cyclones whose topology can be controlled by adjusting the properties of the acoustical beam. In confined geometry, the phase singularity enables ge…
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Acoustical and optical vortices have attracted large interest due to their ability in capturing and manipulating particles with the use of the radiation pressure. Here we show that acoustical vortices can also induce axial vortical flow reminiscent of cyclones whose topology can be controlled by adjusting the properties of the acoustical beam. In confined geometry, the phase singularity enables generating attractive streaming with a flow directed toward the transducer. This opens perspectives for contact-less vortical flow control.
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Submitted 25 July, 2014; v1 submitted 8 May, 2014;
originally announced May 2014.
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Low power sessile droplet actuation via modulated surface acoustic waves
Authors:
Michael Baudoin,
Philippe Brunet,
Olivier Bou Matar,
Etienne Herth
Abstract:
Low power actuation of sessile droplets is of primary interest for portable or hybrid lab-on-a-chip and harmless manipulation of biofluids. In this paper, we show that the acoustic power required to move or deform droplets via surface acoustic waves can be substantially reduced through the forcing of the drops inertio-capillary modes of vibrations. Indeed, harmonic, superharmonic and subharmonic (…
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Low power actuation of sessile droplets is of primary interest for portable or hybrid lab-on-a-chip and harmless manipulation of biofluids. In this paper, we show that the acoustic power required to move or deform droplets via surface acoustic waves can be substantially reduced through the forcing of the drops inertio-capillary modes of vibrations. Indeed, harmonic, superharmonic and subharmonic (parametric) excitation of these modes are observed when the high frequency acoustic signal (19.5 MHz) is modulated around Rayleigh-Lamb inertio-capillary frequencies. This resonant behavior results in larger oscillations and quicker motion of the drops than in the non-modulated case.
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Submitted 8 March, 2012;
originally announced March 2012.
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Droplets displacement and oscillations induced by ultrasonic surface acoustic waves: a quantitative study
Authors:
P. Brunet,
M. Baudoin,
O. Bou Matar,
F. Zoueshtiagh
Abstract:
We present an experimental study of a droplet interacting with an ultrasonic surface acoustic wave (SAW). Depending on the amplitude of the wave, the drop can either experience an internal flow with its contact-line pinned, or (at higher amplitude) move along the direction of the wave also with internal flow. Both situations appear together with oscillations of the drop free-surface. The physica…
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We present an experimental study of a droplet interacting with an ultrasonic surface acoustic wave (SAW). Depending on the amplitude of the wave, the drop can either experience an internal flow with its contact-line pinned, or (at higher amplitude) move along the direction of the wave also with internal flow. Both situations appear together with oscillations of the drop free-surface. The physical origins of the internal mixing flow as well as the drop displacement and surface waves are still not well understood. In order to give insights of the underlying physics involved in these phenomena, we carried out an experimental and numerical study. The results suggest that the surface deformation of the drop can be related as a combination between acoustic streaming effect and radiation pressure inside the drop.
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Submitted 22 February, 2010;
originally announced February 2010.