The essence of this breakthrough lies in the creation and deployment of what the researchers call a multimode photonic lantern (MM PL), a device meticulously engineered using advanced 3D-printing techniques at the microscale. Photonic lanterns traditionally serve as optical interfaces that merge several single-mode inputs into a multimode waveguide. However, this new “N-MM PL” design uniquely accommodates multiple multimode VCSEL sources simultaneously, fundamentally redefining the operational paradigm for photonic lanterns. Unlike their predecessors, these lanterns effectively multiplex dozens of multimode laser outputs while preserving brightness and ensuring highly efficient coupling to multimode fibers.

In practical terms, the team demonstrated remarkable photonic lantern variants capable of integrating the light from 7, 19, and even 37 distinct VCSEL sources. Each VCSEL exhibits complex spatial mode structures, lasing across six spatial modes, which culminates in effective support for up to 222 spatial modes within a single multimode fiber. This massive-scale multiplexing represents a formidable advancement in optical multiplexing capacity, surpassing conventional methods both in scale and efficiency and enabling far more concentrated laser arrays without the typical penalties of alignment complexity or modal mismatch.

The manufacturing process hinges on precision 3D nanoprinting, allowing the creation of devices less than half a millimeter long—a dramatic size reduction compared to conventional bulky beam combining setups. This compact form factor does not sacrifice performance; on the contrary, it delivers exceptionally low insertion losses, registering as minimal as -0.6 dB for the 19-input lantern and a mere -0.8 dB for the 37-input system. Such low losses are critical in maintaining overall system efficiency and brightness, which directly translates into higher power delivery and improved beam quality in applications spanning industrial laser machining, medical laser systems, and advanced telecommunications.

A critical challenge in previous optical beam combining technologies stemmed from coupling inefficiencies and the inability to handle multimode beams generated by high-power VCSEL arrays. Traditional photonic lanterns were intrinsically single-mode, incompatible with the multimode nature of these VCSEL sources. The research team at Hebrew University ingeniously designed an adiabatic transition within the lantern structure, facilitating a seamless and loss-minimized conversion of multiple few-mode laser outputs into a single multimode fiber. This method preserves the modal richness and brightness of the combined beam, avoiding degradation commonly associated with relay lenses or other beam shaping techniques.

The implications of this research extend deeply into optical communications, where the preservation of modal capacity and brightness is paramount for maximizing data throughput and minimizing transmission losses. Indeed, by harnessing a highly scalable, compact, and efficient photonic lantern, fiber networks could achieve significantly enhanced performance without complex infrastructure overhauls. Moreover, the technology introduces a new dimension to high-power laser systems, where managing heat dissipation and beam quality simultaneously remains a stubborn obstacle. This lantern’s ability to combine many high-power sources without sacrificing optical integrity is poised to unlock fresh industrial and research opportunities.

This advancement is the product of insightful collaboration between the Hebrew University, Civan Lasers, and financial backing from the Israel Innovation Authority. Spearheaded by Ph.D. student Yoav Dana under the mentorship of Professor Dan M. Marom, the team’s work crystallizes years of progress in integrated optics, laser physics, and additive manufacturing. The cross-disciplinary expertise allowed for an inventive fusion of theoretical design and experimental validation, culminating in a demonstrator device whose length measures only 470 micrometers—a scale few optical multiplexers can parallel.

From a technical standpoint, the device’s operation relies on precise modal matching between the multimode inputs and the multimode output fiber. Each VCSEL array emits beams composed of multiple spatial modes, which are notoriously challenging to combine without incurring modal dispersion or brightness loss. The MM photonic lantern accomplishes this by implementing an adiabatic taper geometry that gradually transforms the spatial modes’ distributions, thus preserving the spatial coherence and brightness as these modes are delicately funneled into a fiber that supports all these parallel channel modes simultaneously.

This compact lantern also significantly relaxes the alignment precision typically required for coupling multimode beams into fibers. The intricate 3D-printed waveguide structure internally redistributes the optical paths with nanometer accuracy, easing system integration complexity while enhancing robustness against environmental perturbations—an essential feature for real-world deployment in industrial and communication systems often exposed to mechanical and thermal stresses.

The significance of this achievement is not only in the scale or the compactness but also in its practical applicability. By offering a pathway to spatially multiplexed multimode lasers with minimal insertion loss and preserved brightness, the research opens avenues to scalable, high-brightness laser arrays suitable for next-generation laser manufacturing, aerospace optical systems, and secure high-capacity fiber networks. The lantern’s potential to serve as a universal interface between multimode semiconductor lasers and fibers signals a paradigm shift for photonic system design.

Looking forward, scaling this technology further could facilitate even denser laser arrays, dramatically increasing the combined optical power deliverable through fiber networks. Such scalability ensures this innovation is future-proof, accommodating ongoing trends in miniaturization and integration in photonics. Whether applied to boosting fiber optic communication bandwidth or enhancing laser machining precision, the 3D-printed multimode photonic lantern epitomizes the fusion of cutting-edge fabrication techniques with profound optical design principles.

In summary, the Hebrew University research team has presented a transformative solution to a long-standing photonics challenge: efficiently combining the output of many multimode VCSELs into a single fiber with minimal loss and preserved brightness. The microscale 3D-printed multimode photonic lantern breaks new ground in scalability, efficiency, and compactness, promising broad impacts across scientific and industrial photonics. This work illustrates the power of interdisciplinary collaboration and advanced manufacturing to redefine optical technologies for the next wave of innovation.

Subject of Research: Not applicable

Article Title: Massive-scale spatial multiplexing of multimode VCSELs with a 3D-printed photonic lantern

News Publication Date: 10-Mar-2026

Web References: 10.1038/s41467-026-70458-4

Image Credits: Ksenia Shukhin

Keywords

Photonics, Optical materials, Fiber optics, Laser systems, Physics

Metasurfaces, ultra-thin planar structures engineered to manipulate electromagnetic waves precisely, have long been hailed as a transformative platform in optics and photonics. However, when applied to color routing—where different wavelengths corresponding to colors must be spatially separated and directed—conventional metasurfaces suffer from significant efficiency degradation. This is primarily due to spatial multiplexing, a method where multiple functionalities are merged into a single device by partitioning its surface into distinct regions, each responding to a specific color. While functionally useful, this approach inherently divides the available aperture and energy, leading to intrinsic losses and performance limitations.

The research team’s novel strategy leverages the concept of ‘nonlocal’ metasurfaces, which fundamentally diverge from the traditional ‘local’ phase control mechanism. Instead of manipulating light on a point-by-point basis with isolated meta-atoms, nonlocal metasurfaces exploit collective interactions across the entire structure to achieve wavefront shaping with higher efficiency and multifunctionality. This approach preserves the total optical aperture for each color channel, circumventing the classical trade-off between multiplexing and efficiency.

At the heart of this innovation lies a meticulously engineered metasurface design that integrates resonant modes capable of spatially separating red, green, and blue light components without splitting the device area. By controlling the interplay of light within this engineered surface, the device can route each color component to different output ports with minimal losses. This significant enhancement stems from the intrinsic wave interactions engineered through the metasurface’s nonlocal resonances, which contrast sharply with the conventional local responses.

The implications of this advancement are profound. In integrated photonic circuits, efficient color routing is essential for applications ranging from optical communications and imaging systems to augmented reality and display technologies. Traditional spatial multiplexing metasurfaces forced a compromise between device size, efficiency, and color channel isolation, which hindered practical deployment in compact and high-performance systems. The nonlocal metasurface developed here breaks this trade-off by delivering unprecedented efficiency without increasing device complexity or footprint.

In their experimental demonstration, the researchers achieved near-unity efficiency in routing visible colors, marking a staggering improvement over previously reported metasurface-based color routers. This level of efficiency is crucial for real-world applications, where energy constraints and signal integrity define device feasibility. The ability to route multiple colors on a single chip with minimal crosstalk and energy loss presents new avenues for integrated photonics designs that demand precise spectral control.

The theoretical underpinnings of the device were corroborated with rigorous numerical simulations and experimental validations. The team employed advanced electromagnetic modeling techniques to design the nonlocal metasurface such that the tailored resonances selectively couple to different spectral bands. This engineered spectral selectivity, combined with spatial routing properties, constitutes a new paradigm in metasurface design.

Crucially, this work challenges a longstanding benchmark in metasurface research: the trade-off between multiplexing capacity and optical efficiency. By harnessing collective resonant behaviors that extend beyond local interactions, the researchers demonstrate that multifunctional metasurfaces can achieve high performance without the conventional penalties associated with spatial segmentation. This conceptual breakthrough signals new opportunities for designing metasurfaces that manage multiple degrees of freedom simultaneously.

The practical advantages of such an efficient color router extend into photonic integrated circuits where space is at a premium, and component integration density must be maximized. Devices benefiting from this technology could see substantial improvements in size, energy consumption, and bandwidth, addressing key challenges in developing next-generation optical interconnects for data centers, high-resolution displays, and advanced sensing platforms.

Beyond applications, this research contributes substantially to the fundamental understanding of light-matter interaction in artificially structured media. By demonstrating a nonlocal approach practically, the work expands the theoretical landscape of metasurface physics and may inspire new classes of photonic devices that exploit collective modes for enhanced functionality.

This paper also resonates with ongoing efforts to push metasurfaces from laboratory curiosities into commercially viable technologies. The scalable fabrication of the metasurface, compatible with on-chip integration and possibly CMOS processes, suggests a feasible path toward widespread adoption. This aspect is critical to scaling the technology for industrial applications.

The color router’s design flexibility further opens possibilities for dynamic tuning or reconfiguration when combined with active materials or phase-change components. Such developments could lead to adaptive optics and smart photonic systems capable of responding to changing environmental inputs or user demands, all while maintaining high routing efficiencies.

In summary, this discovery not only provides a powerful solution to a vexing problem in photonic engineering but also reshapes the conceptual framework within which metasurfaces can be designed. By conquering the efficiency loss previously deemed unavoidable in spatial multiplexing, the researchers chart a path toward nanoparticles capable of extraordinary multifunctionality, compactness, and performance.

Looking forward, this breakthrough invites a reevaluation of how multifunctionality should be approached in metasurface engineering, encouraging the exploration of collective phenomena instead of segmented design paradigms. The ripple effects of this research might well accelerate the convergence of photonics with information technologies, leading to faster, smaller, and more efficient optical devices that were previously deemed impractical.

Ultimately, this first-of-its-kind on-chip nonlocal metasurface for color routing stands as a beacon for future exploration, offering vast potential across telecommunication, display technology, augmented reality, and beyond. As the field advances, such innovations will be critical stepping stones toward realizing the full promise of metasurface-enabled photonics.

Article References:
Shi, Y., Wan, S., Wang, Z. et al. On-chip nonlocal metasurface for color router: conquering efficiency-loss from spatial-multiplexing. Light Sci Appl 15, 66 (2026). https://doi.org/10.1038/s41377-025-02146-9

Image Credits: AI Generated

DOI: 10.1038/s41377-025-02146-9 (Published 12 January 2026)