In a pioneering leap for ultrasonic wave manipulation, researchers Su, Wang, Gu, and their colleagues have unveiled a novel approach to generating multi-channel ultrasonic Bessel vortex beams via spatial multiplexing metalenses, illuminating new pathways in acoustic engineering. This cutting-edge technology brings together principles of wave physics with advanced material engineering to unlock unprecedented control over ultrasonic fields, promising transformative impacts across communication, medical imaging, and materials science.
Ultrasonic waves, sound waves operating beyond the threshold of human hearing, have long been harnessed for applications ranging from imaging internal organs to non-destructive material testing. However, traditional ultrasonic beam generation methods often face limitations in beam shaping and multiplexing, constraining their efficacy and versatility. The introduction of metalenses—ultra-thin, planar lenses engineered from metasurfaces capable of manipulating waves at sub-wavelength scales—revolutionizes this landscape by enabling not only precise wavefront control but also the multiplexing of distinct beam profiles simultaneously.
At the heart of this breakthrough is the creation of Bessel vortex beams, a class of structured waves characterized by their non-diffracting and self-healing properties, as well as their intrinsic orbital angular momentum. Unlike conventional Gaussian beams, Bessel beams maintain their intensity profile over extended distances and can reconstruct themselves after encountering obstacles, attributes highly desirable for robust signal transmission and precise material interaction. The added dimension of vortex topology endows these beams with twisted wavefronts, enhancing their potential for multiplexed communication channels and particle manipulation.
The researchers harnessed spatial multiplexing strategies within a single metalens platform to generate multiple ultrasonic Bessel vortex beams concurrently. This achievement stems from a meticulous design of the metalens’ metasurface—an array of nano- or micro-scale unit cells—where each substructure imposes specific phase and amplitude modulations on the incoming ultrasonic waves. By spatially encoding different phase profiles across the metalens, the device effectively acts as a wavefront synthesizer capable of producing several independent beams with distinct properties simultaneously.
In practical terms, the multi-channel capability expands the information capacity of ultrasonic systems, heralding a new era of parallel acoustic communications. This technological advancement could allow for multiple data streams to be transmitted simultaneously through acoustic channels, which is profoundly significant in environments where radiofrequency signals are impractical or prohibited, such as underwater communication or sensitive medical procedures.
Further, the intrinsic self-healing nature of ultrasonic Bessel vortex beams lends resilience to the generated channels against environmental perturbations and scattering, a common challenge in complex media. By integrating this with the multiplexed output of the metalens, stable, high-fidelity communication and imaging systems become achievable, overcoming traditional barriers posed by turbulence or heterogeneous material structures.
From a fabrication perspective, the metalens designed by Su and colleagues utilizes cutting-edge microfabrication techniques suitable for ultrasonic wavelengths, ensuring compatibility with existing ultrasonic transducer technologies. The planar form factor and integrability of the metalens enable seamless incorporation into compact device architectures, promoting miniaturization of ultrasonic systems without compromising beam quality or multiplexing efficiency.
Moreover, the approach offers reconfigurability potential by tailoring the metalens structures or combining them with active materials, paving the way for dynamic beam shaping and adaptive acoustic systems. Such capabilities could revolutionize medical ultrasonography by enabling highly customizable beam patterns tailored to patient-specific diagnostic requirements, enhancing resolution while minimizing exposure.
The team’s theoretical and computational modeling highlights the interplay between the metasurface unit cell geometry and the resultant ultrasonic beam characteristics, providing a comprehensive framework to engineer bespoke acoustic fields. This model serves as a crucial tool for designing application-specific ultrasonic devices, ranging from precision manipulation in microfluidics to targeted energy delivery in therapeutic ultrasound.
Importantly, the research unearths fundamental insights into the propagation dynamics of multiplexed ultrasonic Bessel vortex beams, revealing how beam overlap, interference, and mode coupling influence the overall system performance. Understanding these complex interactions is paramount for optimizing signal integrity and minimizing cross-talk between channels, critical factors for practical deployment.
The innovation also extends beyond communication and imaging; the precise control over acoustic vortex beams unlocks possibilities for novel particle trapping and manipulation techniques in acoustic tweezers technology. This can have profound applications in biology and materials science where non-contact manipulation of microscopic entities is essential.
As the metalens technology matures, integration with real-time control electronics and machine learning algorithms could foster self-optimizing acoustic systems. These systems would adapt beam properties on-the-fly to environmental changes or operational demands, increasing robustness and efficiency in a multitude of settings.
Furthermore, the environmental implications of this technology merit attention. Ultrasonic communication and sensing traditionally consume significant power and often require bulky devices. The compact, efficient design of the spatial multiplexing metalens could reduce energy consumption and device footprint, aligning with sustainable engineering goals.
The research conducted by Su, Wang, Gu, et al. exemplifies a harmonious synthesis of metamaterials science, wave physics, and engineering ingenuity, setting a precedent for future explorations into multifunctional acoustic devices. Their work not only expands the toolkit for ultrasonic beam engineering but also stimulates a broader discourse on the integration of advanced metastructures in practical acoustic technologies.
In summary, this groundbreaking work on multi-channel ultrasonic Bessel vortex beams produced by spatial multiplexing metalenses marks a significant milestone in acoustic science, promising to reshape the landscape of ultrasonic devices. Its blend of theoretical sophistication and practical applicability sets a high bar for innovations in wave-based communication, imaging, and manipulation technologies in the coming decade.
Subject of Research: Acoustic wave manipulation using spatial multiplexing metalenses to generate multi-channel ultrasonic Bessel vortex beams.
Article Title: Multi-channel ultrasonic Bessel vortex beams by spatial multiplexing metalens.
Article References:
Su, Y., Wang, D., Gu, Z. et al. Multi-channel ultrasonic Bessel vortex beams by spatial multiplexing metalens. Commun Eng (2026). https://doi.org/10.1038/s44172-026-00599-3
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