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Topological Jackiw-Rebbi States in Photonic Van der Waals Heterostructures

19 July 2026 at 04:08

A new study is turning an elegant quantum idea into a practical platform for light. In research published in Light: Science & Applications, physicists report “topological Jackiw–Rebbi” states engineered inside photonic van der Waals heterostructures—systems built by stacking atomically thin materials with precisely tailored interfaces. The result is a photonic phenomenon that echoes how particles can be trapped at boundaries where the rules of their governing equations change.

The work builds on the classic Jackiw–Rebbi mechanism, originally proposed for relativistic particles. In those models, a localized mode appears when a mass term flips sign, effectively creating a domain wall. The authors translate this concept into optics by designing photonic structures where an effective “mass” characterizing light propagation changes across an interface.

What makes the platform especially compelling is the van der Waals architecture. Unlike conventional fabrication routes that can introduce disorder, the layered nature of these materials enables sharp, controllable boundaries and tunable photonic band structures. By adjusting the stacking and interlayer optical responses, the researchers create conditions in which topological modes become robust against typical imperfections.

The study emphasizes that these states are not merely conventional guided resonances. Instead, they are tied to topology: the light modes are associated with an invariant property of the band structure. As a consequence, the Jackiw–Rebbi-like photonic states are expected to persist even when the system’s details vary, so long as the relevant symmetry and band configuration remain intact.

Topological protection is more than a slogan. In photonics, it can translate into reduced sensitivity to fabrication tolerances and a pathway toward devices that rely on stable boundary transport. The paper therefore positions these localized states as building blocks for future optical components that route signals along designed interfaces.

The authors demonstrate the concept theoretically and connect it to experimental observables by focusing on how the interface should host modes localized near the domain wall region. Such localization is a hallmark of the Jackiw–Rebbi scenario, now realized in a controllable, designer photonic environment.

Beyond fundamental interest, the approach could influence the design of reconfigurable photonic circuits. Because van der Waals stacks can be combined and adjusted, the same topology-driven logic may be extended to new material systems, wavelengths, and device geometries.

Overall, the report signals a broader trend: using topological field-theory ideas to engineer light–matter behavior in atomically precise platforms, potentially enabling the next generation of robust, interface-based photonic technologies.

Subject of Research: Topological photonic states (Jackiw–Rebbi) in van der Waals heterostructures.

Article Title: Topological Jackiw-Rebbi states in photonic Van der Waals heterostructures.

Article References: Randerson, S.A., Bouteyre, P., Hu, X. et al. Light Sci Appl 15, 323 (2026). https://doi.org/10.1038/s41377-026-02392-5

Image Credits: AI Generated

DOI: 10.1038/s41377-026-02392-5

Keywords:

We tested Canon’s $10,000 wildlife zoom — can it replace a prime lens?

15 July 2026 at 17:00

When it comes to the "silly money" category of lenses, they are typically those ridiculously long prime lenses that make your arms ache just by looking at them. They provide incredible image quality but lack the versatility of a zoom. Enter the Canon RF 100-300mm f/2.8L IS USM: With a constant f/2.8 aperture throughout the entire 100-300mm focal range, this lens is a serious contender for wildlife pros and sports photographers.

Of course, at an eye-watering $10,500, it's not for everyone. It's not even for "many people"; it's for a select few who either have serious money lying around or make serious money from photography, where a lens of this caliber would be a sensible investment. Still, we took it for a test drive to see just how much better the performance is compared to the more reasonably priced wildlife zoom lenses.

Canon RF 100-300mm f/2.8L IS USM: Design

Canon RF 100-300mm f/2.8L IS USM lens against green foliage
Kimberley Lane
Canon RF 100-300mm f/2.8L IS USM lens against green foliage
Kimberley Lane
Canon RF 100-300mm f/2.8L IS USM lens against green foliage
Kimberley Lane
  • Weight is surprisingly manageable
  • Internal zoom
  • Solid and sturdy build quality

Although its weight is comparable to that of the much cheaper SIGMA 60-600mm Sport lens we tested recently, this lens from Canon is actually the lightest f/2.8 300mm lens on the market. And because the zoom is internal, the weight distribution feels much more manageable in the smaller package than it does on a lens that extends. (But that’s not to say our arms weren’t aching the following day).

It's also dust- and weather-resistant, which we’d expect on a lens that's this expensive. It's solid and sturdy with a plethora of lens coatings to eliminate glare and ghosting, and it feels every bit the professional-grade Canon L lens you would want.

It comes with plenty of buttons and switches on the barrel, including the standard AF/MF switch, focus limiter and IS on/off. It has another switch to choose between three stabilization modes (mode 1 for static subjects, mode 2 for panning and mode 3 for tracking erratic moving subjects).

The final switch is a focus preset button, which enables you to pre-focus on a certain spot where you expect the action to be, then switch back and forth as you're shooting. Alternatively, you can set this switch to L-Fn to utilize it as a programmable function button instead.

Key specs:

Type: Canon full frame, mirrorless
Focal length: 100-300mm
Aperture: Constant f/2.8
Close focusing distance: 5.9 feet / 1.8 m (constant)
Image stabilization: 5.5 stops
Filter thread: 112 mm
Dimensions: 5.04 x 12.73 inches / 128 x 323.4 mm
Weight: 5.7 lbs / 2,590 g

This lens isn't expensive because it introduces any revolutionary build features. It's expensive because Canon has combined every premium design element — internal zoom, magnesium construction, professional weather sealing, compact packaging and meticulous engineering into a lens that is designed to meet the needs of professional photographers.

Canon RF 100-300mm f/2.8L IS USM: Performance

happy red panda sat in a tree
Kimberley Lane
red panda peering over a tree branch
Kimberley Lane
happy red panda sat in a tree
Kimberley Lane
golden labrador looking to the side
Kimberley Lane
brown dog looking to the side
Kimberley Lane
giraffe with its tongue out
Kimberley Lane
  • Outstanding image quality
  • Basically no image defects
  • Beautiful bokeh

Image quality is, unsurprisingly, absolutely beautiful. The shots we took are razor-sharp and clean with basically no defects whatsoever. There's a tiny bit of distortion, which is easily corrected in Lightroom (and wouldn't be detectable unless you were directly comparing the before/afters), but the images have no chromatic aberration or vignetting at all.

This lens shows every strand of fur or feather and effortlessly captures the moment perfectly every time. The bokeh is soft and creamy thanks to the constant f/2.8 aperture, which beautifully isolates the subject and blurs out distracting background elements.

We took images at f/2.8, f/4, f/5.6, f/8 and f/11 at 100mm, 200mm and 300mm to see how the lens performs across a variety of settings. Looking at the center portion of our test chart shots, the sharpest images are f/5.6 at 100mm, f/2.8 at 200mm and f/2.8 at 300mm. At 100mm, our f/2.8, f/4 and f/5.6 shots were all of similar quality in terms of central sharpness, but f/5.6 has the edge when it comes to contrast.

Those same three apertures were also very similar at 200mm, but in this instance, f/2.8 has the edge. At 300mm, there was a significant drop in contrast between f/2.8 and f/4, but both images were of similar sharpness. Unsurprisingly, the corners were sharpest towards the f/8 range, but wildlife photography rarely ever calls for sharpness across the entire frame, so the softer corners at f/2.8 - f/5.6 aren't a dealbreaker.

Canon RF 100-300mm f/2.8L IS USM: Functionality

sausage dog stood next to a stream
Kimberley Lane
red panda walking along a tree branch
Kimberley Lane
brown dog looking to the side
Kimberley Lane
red panda climbing on tree branches
Kimberley Lane
giraffe looking to the side
Kimberley Lane
meerkat sat in the shade
Kimberley Lane
  • Constant f/2.8 aperture throughout the whole zoom range
  • 5.5 stops of image stabilization
  • Versatile focal length and teleconverter compatibility

A big selling point with this type of lens is the constant f/2.8 aperture throughout the entire focal range — and this is a common feature with many lenses at this price range. The wide aperture allows for faster shutter speeds, which is ideal for capturing sharp images of fast-moving wildlife or sports photography, and the wide aperture also increases light intake in low-light situations, like photographing animals at dawn or dusk or indoor sports.

Although the 100-300mm focal length wouldn't be the best choice for photographing small birds or distant subjects, it provides a good focal range to cover many other types of wildlife, like equine or safari photography, as well as a variety of indoor sports. While it's not the biggest zoom range on offer, it eliminates the need to switch between lenses while on a shoot.

This, in turn, means faster reactions to changing scenes, less chance of missing shots when the subject moves unexpectedly and better protection from dust and rain due to less swapping. Plus, when paired with the Canon 1.4x teleconverter, this lens becomes a 140-420mm f/4, and a 200-600mm f/5.6 with the 2x extender, opening up the possibilities even further.

With the lens's 5.5 stops of image stabilization (which increases to 6 stops when paired with EOS R cameras with IBIS), this lens has no trouble following fast-moving subjects smoothly and efficiently — which is useful for both image quality and viewfinder steadiness.

Should you buy the Canon RF 100-300mm f/2.8L IS USM?

author Kimberley Lane using the Canon R6 III and Canon RF 100-300mm f/2.8L IS USM lens in a wooded area

(Image credit: Kimberley Lane)

It feels counterintuitive to give this lens 5 stars but say "no, don't buy it," and it's not that we're saying "don't buy it," but as good as this lens is, it's quite niche, and we are finding it hard to justify the price compared to other setups from Canon.

Currently, this lens is the only way to get 300mm at f/2.8 (unless you get a used EF 300mm f/2.8L IS II USM and an EF-EOS R adapter), so unless you really need to shoot between 200-300mm at f/2.8 and have the money to do so, there are more sensible options that either save money or give you more value.

For example, you could buy an R1 and a used EF 300mm f/2.8L lens with an adapter for around the same price as this 100-300mm lens. And if you find good deals, you could even add the Canon RF 70-200mm f/2.8L IS II USM to that lineup with a teleconverter. The only advantage the 100-300mm would then have is that you wouldn't need to change lenses — but is that worth such a steep price?

If this lens isn't for you

Canon RF 600mm f/2.8L IS USM on a white backgroundFor serious birders

Canon RF 600mm f/4L IS USM

For birds or distant wildlife, the Canon RF 600mm f/4L IS USM lens will be more appropriate. Although you lose a bit of aperture at the wide end, it won't make too much difference in practice, and the longer reach makes this lens much more suitable for photographing birds.

Canon RF 70-200mm f/2.8L IS USM on a white backgroundIf you want a cheaper telephoto zoom

Canon RF 70-200mm f/2.8L IS USM

For photographers who don't need 300mm very often and want to save several thousand dollars, the Canon RF 70-200mm f/2.8L IS USM covers up to 200mm and also has a constant f/2.8 aperture. Plus, it's a lot lighter and more compact.

Canon RF 200-800mm F6.3-9 IS USM on a white backgroundIf you prioritize reach over speed

Canon RF 200-800mm f/6.3-9 IS USM

If you photograph distant subjects or small birds in good light and you need more reach, the Canon RF 200-800mm f/6.3-9 IS USM has the most reach of any Canon zoom and produces beautiful images.

Read our full Canon RF 200-800mm f/6.3-9 IS USM review

Canon EOS R6 III review: A wildlife wonder

10 July 2026 at 13:00

The Canon EOS R6 III is Canon's newest full-frame camera. We absolutely loved the R6 II when we reviewed it, and the Mark III's improved 32.5MP resolution, 7K video capability and CFexpress compatibility build on that strong foundation to take this camera from the beginner and enthusiast level straight into the serious intermediate camera category.

We primarily tested it for wildlife photography with Canon's 100-300mm f/2.8L IS USM lens, but the R6 III is such an impressive all-rounder, it can easily turn its hand to astrophotography, sports or event photography, too.

Canon EOS R6 III: Design

Canon EOS R6 III
Kimberley Lane
Canon EOS R6 III
Kimberley Lane
Canon EOS R6 III
Kimberley Lane
Canon EOS R6 III
Kimberley Lane
Canon EOS R6 III
Kimberley Lane
  • Comfortable grip to accommodate larger lenses
  • Identical layout to previous model
  • One SD card slot, one CFexpress card slot

Existing Canon users will feel right at home with the Canon EOS R6 III, as the build and button layout are nearly identical to the R6 II, and similar to many other R-series bodies. We tested the R6 III with the Canon RF 100-300mm f/2.8L IS USM lens and found it comfortable to get a good grip on, and it feels satisfying in the hand, especially when paired with bigger lenses.

Key specs:

Type: Mirrorless, full-frame
Resolution: 32.5 megapixels
Burst rate: 12fps mechanical, 40fps electronic
Image stabilization: 8.5 stops
Weight: 1.54 pounds / 699 g (with battery and card)
Battery life: 620 shots (CIPA)

The LCD screen and viewfinder are exactly the same as the Mark II, but there are a couple of small differences elsewhere in the design. The R6 III now has a CFexpress Type B card slot as well as an SD card slot, allowing for faster workflows and data transfer. However, considering this camera sits in the more intermediate level, we have to question whether two SD slots would be more useful for the majority of users, especially because CFexpress cards are more expensive. Plus, we used fast SD cards during our tests and encountered no problems at all with the write speed or buffer.

Canon EOS R6 III: Performance

smiling red panda climbing on tree branches
Kimberley Lane
sausage dog against grey stones
Kimberley Lane
yellow bird sat on a log
Kimberley Lane
red panda walking across tree branches
Kimberley Lane
lemur's face over a wooden shelf
Kimberley Lane
brown bear looking up to the sky
Kimberley Lane
golden labrador shaking water off its body
Kimberley Lane
giraffe eating straw
Kimberley Lane
  • An absolute joy for wildlife photography
  • 32.5MP sensor is a very welcome improvement over the Mark II
  • Autofocus and subject detection are accurate and sticky

The Canon EOS R6 III features more advanced AI-powered autofocus, which enables it to track people, animals and vehicles more easily compared with the Mark II. When we were photographing animals at a zoo, the autofocus was generally very good, although there were a few occasions when the camera got confused. The focus jumped between the giraffe’s eyes, nostrils and ossicones, and the camera couldn’t quite figure out what to focus on, even when the animal was facing towards the camera with the eyes in view. There were also a few unfortunate occasions when the camera would find and track an "eye" on the — how do we put this — wrong end of the animal. Generally, though, it was fast and accurate.

In our review of the previous model, the Canon EOS R6 II, we said, "Considering it's the next step up from the Canon EOS R8, we'd hoped for a bump in resolution. Matching the 32.5MP resolution of the crop-sensor Canon R7 would have given the R6 II an even sweeter spot between the R8 and the 45MP powerhouse Canon EOS R5 II." It seems Canon was listening, as the 32.5MP sensor in the Canon EOS R6 III sits perfectly between the beginner and professional lineups. The images are clean, detailed and not too noisy, making this camera a compelling choice for photographic styles that require excellent resolution without excessive noise.

Canon EOS R6 III: Functionality

red panda about to eat leaves
Kimberley Lane
giraffe eating straw
Kimberley Lane
winking red panda amongst green foliage
Kimberley Lane
meerkat stood on a rock
Kimberley Lane
red panda eating leaves
Kimberley Lane
meerkat lying down
Kimberley Lane
red panda in a tree
Kimberley Lane
  • Canon claims battery life allows for around 620 shots (CIPA) — we took around 6,000
  • Blackout-free burst shooting up to 40FPS
  • Pre-continuous shooting

For wildlife photography, blackout-free shooting enables you to follow the subject a lot easier as it's moving, to ensure you can keep the subject centered and maintain your composition. What's more, with the R6 III, you can shoot up to a massive 40 frames per second (FPS) blackout-free, which is perfect for fast-moving wildlife. (Keep in mind, this means you need to hone your timing to avoid the "spray and pray" method and end up with tons of photos of the exact same moment). This is one feature of a wildlife camera that makes a big difference.

The R6 III also features pre-continuous shooting, where it'll record up to 20 frames (approx 0.5 seconds) before the shutter is fully pressed — another useful feature for wildlife and sports photographers who need to capture fleeting moments.

The Mark III uses the upgraded LP-E6P battery, shared with the R5 II, which offers significantly more shots per charge than the LP-E6NH in the R6 II. That said, it means that if you're upgrading from a different Canon model, your current spare batteries won't work in the R6 III, so you'll need to invest in a few spares. However, we managed to get more than 6,000 photos without having to swap out the battery, so you won't need to worry about the battery running out unless you're shooting all day for multiple days.

Should you buy the Canon EOS R6 III?

We can confidently say: yes, you should buy it. It seems to tick all the boxes for a lot of shooting scenarios, whether it's your main wildlife camera or a backup body for weddings. The 32.5MP sensor produces beautiful images with minimal noise and accurate color reproduction; it's lightning fast with a 40FPS burst speed and can capture up to 7K 60p video. However, if you're looking for a more serious pro-level camera, perhaps opt for the R1 or R3 instead.

If this camera isn't for you

Canon EOS R1 on a white backgroundIf you want to go pro

Canon EOS R1

If you're looking for a professional body with maximum reliability, professional-level handling and overall increased performance, look at the Canon EOS R1.

Canon EOS R7 on a white backgroundIf you're a beginner

Canon EOS R7

Beginners or anyone on a budget should consider the Canon EOS R7. It has the same 32.5MP resolution, a 30FPS burst rate, and the APS-C sensor applies a 1.6x crop factor when paired with a full-frame lens to increase reach.

Read our full Canon EOS R7 review

Canon EOS R5 IIIf you want more resolution

Canon EOS R5 Mark II

The Canon EOS R5 II has a higher 45MP resolution with a stacked sensor, 8K video and a decreased but still impressive 30FPS burst rate.

Read our full Canon EOS R5 II review

Breakthrough in Optical Computing: Introducing the Digital Twin System

16 June 2026 at 13:49

In the rapidly evolving realm of artificial intelligence and deep learning, conventional electronic computing architectures are increasingly strained by the demands of large-scale data processing and intricate computational tasks. Optical computing has risen as a compelling alternative, leveraging the inherent physical phenomena of light—such as interference and diffraction—to execute computations fundamentally differently from traditional electronics. By harnessing these optical effects, optical computing systems (OCS) promise unparalleled advantages: notably superior processing speeds, heightened energy efficiency, and a natural aptitude for massive parallelism. These attributes make optical computing especially attractive for intensive applications like image processing, machine learning, and big data analytics, holding transformative potential across these domains.

Yet, despite these promising characteristics, contemporary optical computing platforms grapple with a significant bottleneck rooted in their hardware-centric development workflows. Conventionally, researchers must directly engage with physical OCS hardware to develop, tune, and validate computational tasks. This process entails sequential access to a limited number of costly and often heavily utilized devices. Users must physically occupy the system to load parameters, fine-tune configurations, and iteratively calibrate the hardware—an intrinsically tedious and time-consuming cycle. Each new user or task demands resetting the system state, leading to protracted queues, repetitive adjustments, and redundant calibrations. The resulting workflows impose long hours of equipment occupation and elevated trial-and-error expenses, stifling the possibility for concurrent task development and drastically curtailing research throughput and system agility.

To surmount these entrenched challenges, cutting-edge research has introduced the concept of the Digital Twin Optical Computing System (DT-OCS). This innovative approach establishes a high-fidelity digital replica—a “digital twin”—of the physical OCS that accurately models its input-output behavior under varying configuration parameters. Crucially, the digital twin allows researchers to perform extensive offline simulations, training, and optimization without the constraints of physical hardware availability. Analogous to a digital simulator software that mirrors a complex “real machine,” DT-OCS enables extensive task development and parameter tuning within a virtual environment, dramatically decoupling software development from hardware dependency. Consequently, optimized parameters validated digitally can be seamlessly transferred back to the physical system for deployment, bypassing numerous iterative hardware trials.

The implications of DT-OCS extend well beyond mere time savings. By effectively creating a “digital development toolkit” for optical computing, this framework revolutionizes the research ecosystem—transforming optical computing platforms from isolated, hardware-bound experiments to versatile, shareable research infrastructures. Researchers can now conduct task training, performance benchmarking, and method comparisons entirely within a unified digital realm, fostering collaborative innovation. Distinguished from legacy OCS paradigms, DT-OCS supports parallel task development workflows, allowing multiple computational problems to be advanced simultaneously without hardware conflicts. This capability markedly enhances flexibility, reduces development bottlenecks, and accelerates the maturation and practical adoption of optical computing technologies.

Envisioning the trajectory of optical computing, the integration of digital twin models with physical hardware appears indispensable. Contemporary transportation systems, for instance, benefit from the synergy between tangible road networks and dynamic digital mapping platforms. Similarly, next-generation optical computing platforms should embody dual representations: a robust physical computing infrastructure supplemented by perpetually updated digital twins. This paradigm champions accessibility, reproducibility, and scalability—cornerstones for fostering broad-scale collaboration. It paves the way for unified validation standards and equitable performance comparisons, catalyzing optical computing’s evolution into a general-purpose, widely deployable resource rather than a niche experimental setup.

The DT-OCS framework’s hallmark is its strategic decoupling of task development from hardware constraints. In traditional optical computing, task training and parameter fine-tuning necessitate iterative hardware engagements involving adjustments, diagnostics, and recalibrations. This approach encumbers the process with inefficiencies and precludes simultaneous multi-task development. DT-OCS obviates these impediments by faithfully modeling the physical system’s responses across parameter spectra, enabling exhaustive offline optimization. This digital-first workflow increases research agility, minimizes hardware occupancy, and substantially compresses the development timeline. Consequently, DT-OCS amplifies the throughput and adaptability of optical computing research endeavors.

The real-world efficacy of the DT-OCS framework has been experimentally validated using a cutting-edge high-speed optical computing system incorporating silicon photonic feature-computing chips. These empirical studies demonstrated DT-OCS applications in diverse computational domains, including image classification and sequential decision-making. Notably, configurations optimized within the digital twin translated flawlessly to the physical hardware, with observed task performance closely mirroring digital forecasts. This underscores not only the high fidelity of the DT-OCS model but also its robust transferability across practical scenarios. Moreover, by enabling parallel task development within the digital domain, DT-OCS expedites the overall research workflow, markedly elevating efficiency.

An illustrative application of the DT-OCS system involved offline training and deployment for the Fashion-MNIST image classification task—a benchmark dataset widely used in machine learning. This practical demonstration affirms DT-OCS’s capacity to bridge digital model development with real-world optical computing implementations. Beyond efficiency gains, DT-OCS signifies a conceptual shift toward disentangling computational task design from the idiosyncrasies of physical system constraints. Historically, optical computing research has been hamstrung by its dependence on specific hardware platforms and accessibility limitations, hindering reproducibility and cross-task comparisons. The introduction of an open-source digital twin framework surmounts these barriers by democratizing access and standardizing evaluation protocols.

By openly releasing the DT-OCS framework alongside associated task datasets, the research fosters a community-driven ecosystem where software-based task design, training, and validation can proceed independently of physical system constraints. This openness engenders scalability, reproducibility, and collaborative potential that traditional optical computing architectures cannot easily achieve. Researchers worldwide gain the freedom to explore broader task horizons, perform comprehensive benchmarking, and validate innovative approaches within a consistent computational substrate. Such a paradigm shift propels optical computing from isolated experimental configurations into accessible and extensible platforms, expediting technological advancements and practical deployments.

This pioneering work advocates a transformative application paradigm for optical computing platforms: the symbiotic coexistence of physical hardware and computationally equivalent open-source digital twin models. Only by embracing such dual-system architectures can the field transcend limitations imposed by experimental variability and hardware scarcity. The resultant platforms will be shareable, replicable, and adaptable to a diverse array of research challenges. As optical computing moves towards becoming a mainstream computational resource, the principles embodied by DT-OCS may well establish the foundational infrastructure that underpins scalable, collaborative innovation in photonic information processing.


Subject of Research: Not applicable

Article Title: Digital twin optical computing system

News Publication Date: 21-Apr-2026

Web References:

References:
DOI: 10.29026/oea.2026.250254

Image Credits: Dr. Tingzhao Fu from the National University of Defense Technology, China, and Dr. Hongwei Chen from Tsinghua University, China


Keywords

Artificial intelligence, Computer science, Photonics, Engineering, Machine learning, Computer modeling, Computer processing, Semiconductors, Optics, Applied optics

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