As the fundamental flaw of today’s quantum computers, improving qubit stability remains the focus of much research in this field. One such stability attempt involves so-called topological quantum computing with the use of anyons, which are two-dimensional quasiparticles. Such an approach has been claimed by Microsoft in a recent paper in Nature. This comes a few years after an earlier claim by Microsoft for much the same feat, which was found to be based on faulty science and hence retracted.

The claimed creation of anyons here involves Majorana fermions, which differ from the much more typical Dirac fermions. These Majorana fermions are bound with other such fermions as a Majorana zero mode (MZM), forming anyons that are intertwined (braided) to form what are in effect logic gates. In the Nature paper the Microsoft researchers demonstrate a superconducting indium-arsenide (InAs) nanowire-based device featuring a read-out circuit  (quantum dot interferometer) with the capacitance of one of the quantum dots said to vary in a way that suggests that the nanowire device-under-test demonstrates the presence of MZMs at either end of the wire.

Microsoft has a dedicated website to their quantum computing efforts, though it remains essential to stress that this is not a confirmation until their research is replicated by independent researchers. If confirmed, MZMs could provide a way to create more reliable quantum computing circuitry that does not have to lean so heavily on error correction to get any usable output. Other, competing efforts here include such things as hybrid mechanical qubits and antimony-based qubits that should be more stable owing to their eight spin configurations.

While not impossible, replicating the machines and processes of a modern semiconductor fab is a pretty steep climb for the home gamer. Sure, we’ve seen it done, but nanoscale photolithography is a demanding process that discourages the DIYer at every turn. So if you want to make semiconductors at home, it might be best to change the rules a little and give something like this pulsed laser deposition prototyping apparatus a try.

Rather than building up a semiconductor by depositing layers of material onto a silicon substrate and selectively etching features into them with photolithography, [Sebastián Elgueta]’s chips will be made by adding materials in their final shape, with no etching required. The heart of the process is a multi-material pulsed laser deposition chamber, which uses an Nd:YAG laser to ablate one of six materials held on a rotating turret, creating a plasma that can be deposited onto a silicon substrate. Layers can either be a single material or, with the turret rapidly switched between different targets, a mix of multiple materials. The chamber is also equipped with valves for admitting different gases, such as oxygen when insulating layers of metal oxides need to be deposited. To create features, a pattern etched into a continuous web of aluminum foil by a second laser is used as a mask. When a new mask is needed, a fresh area of the foil is rolled into position over the substrate; this keeps the patterns in perfect alignment.

We’ve noticed regular updates on this project, so it’s under active development. [Sebastián]’s most recent improvements to the setup have involved adding electronics inside the chamber, including a resistive heater to warm the substrate before deposition and a quartz crystal microbalance to measure the amount of material being deposited. We’re eager to see what else he comes up with, especially when those first chips roll off the line. Until then, we’ll just have to look back at some of [Sam Zeloof]’s DIY semiconductors.

One can 3D print with conductive filament, and therefore plausibly create passive components like resistors. But what about active components, which typically require semiconductors? Researchers at MIT demonstrate working concepts for a resettable fuse and logic gates, completely 3D printed and semiconductor-free.

Now just to be absolutely clear — these are still just proofs of concept. To say they are big and perform poorly compared to their semiconductor equivalents would be an understatement. But they do work, and they are 100% 3D printed active electronic components, using commercially-available filament.

How does one make a working resettable fuse and transistor out of such stuff? By harnessing thermal expansion, essentially.

The conductive filament the researchers used is Electrifi by Multi3D, which is PLA combined with copper micro-particles. A segment printed in this filament is normally very conductive due to the densely-packed particles, but as temperature increases (beginning around 40° C) the polymer begins to soften and undergoes thermal expansion. This expansion separates the copper particles, causing a dramatic increase in electrical resistance as electrical pathways are disrupted. That’s pretty neat, but what really ties it together is that this behavior is self-resetting, and reversible. As long as the PLA isn’t straight up melted (that is to say, avoids going over about 150° C) then as the material cools it contracts and restores the conductive pathways to their original low-resistance state. Neat!

So where does the heat required come from? Simply passing enough current through the junction will do the job. By carefully controlling the size and shape of traces (something even hobbyist filament-based 3D printers are very good at) this effect can be made predictable and repeatable.

The simpler of the two test components uses the resistance spike as a self-resetting fuse. The printed component is designed such that current above a threshold triggers a surge in resistance, preventing damage to some theoretical circuitry downstream. As long as the component is not destroyed by heating it to the point that it melts, it self-resets as it cools.

The transistor is a bit more interesting. By designing two paths so that they intersect each other, one can be used as a control path and the other as a signal path. Applying a voltage to the control path electrically controls the resistance of the signal path, effectively acting as a transistor. Researchers combined these basic transistors into NOT, AND, and OR gates. One is shown here.

This whole system is scalable, low-cost, and highly accessible to just about anyone with some basic equipment. Of course, it has some drawbacks. The switching speed is slow (seconds rather than nanoseconds) and being thermally-driven means power consumption is high. Still, it’s pretty nifty stuff. Check out the research paper for all the nitty-gritty details.

We’ve seen 3D printed triboelectric generators so it’s pretty exciting to now see printed active electronic components. Maybe someday they can be combined?

Although the Earth’s magnetic field is reliable enough for navigation and is also essential for blocking harmful solar emissions and for improving radio communications, it’s not a uniform strength everywhere on the planet. Much like how inconsistencies in the density of the materials of the planet can impact the local gravitational force ever so slightly, so to can slight changes impact the strength of the magnetic field from place to place. And it doesn’t take too much to measure this impact on your own, as [efeyenice983] demonstrates here.

To measure this local field strength, the first item needed is a working compass. With the compass aligned to north, a magnet is placed with its poles aligned at a right angle to the compass. The deflection angle of the needle is noted for varying distances of the magnet, and with some quick math the local field strength of the Earth’s magnetic field can be calculated based on the strength of the magnet and the amount of change of the compass needle when under its influence.

Using this method, [efeyenice983] found that the Earth’s magnetic field strength at their location was about 0.49 Gauss, which is well within 0.25 to 0.65 Gauss that is typically found on the planet’s surface. Not only does the magnetic field strength vary with location, it’s been generally decreasing in strength on average over the past century or so as well, and the poles themselves aren’t stationary either. Check out this article which shows just how much the poles have shifted over the last few decades.

One of the problems with quantum bits, or “qubits”, is that they tend to be rather fragile, with a high sensitivity to external influences. Much of this is due to the atoms used for qubits having two distinct spin states of up or down, along with the superposition. Any disturbing of the qubit’s state can cause it to flip between either spin, erasing the original state. Now antimony is suggested as a better qubit atom by researchers at the University of New South Wales in Australia due to it having effectively eight spin states, as also detailed in the university press release along with a very tortured ‘cats have nine lives’ analogy.

For the experiment, also published in Nature Physics, the researchers doped a silicon semiconductor with a single antimony atom, proving that such an antimony qubit device can be manufactured, with the process scalable to arrays of such qubits. For the constructed device, the spin state is controlled via a transistor constructed on top of the trapped atom. As a next step a device with closely spaced antimony atoms will be produced, which should enable these to cooperate as qubits and perform calculations.

By having the qubit go through many more states to fully flip, these qubits can potentially be much more stable than contemporary qubits. That said, there’s still a lot more research and development to be done before a quantum processor based this technology can go toe-to-toe with a Commodore 64 to show off the Quantum Processor Advantage. Very likely we’ll be seeing more of IBM’s hybrid classical-quantum systems before that.

Sometimes you come across a purported scientific paper that makes you do a triple-check, just to be sure that you didn’t overlook something, as maybe the claims do make sense after all. Such is the case with a recent publication in the Langmuir journal by [Budlayan] and colleagues titled Droplet-Scale Conversion of Aluminum into Transparent Aluminum Oxide by Low-Voltage Anodization in an Electrowetting System.

Breaking down the claims made and putting them alongside the PR piece on the [Ateneo De Manila] university site, we start off with a material called ‘transparent aluminium oxide’ (TAlOx), which only brings to mind aluminium oxynitride, a material which we have covered previously. Aluminium oxynitride is a ceramic consisting of aluminium, oxygen and nitrogen that’s created in a rather elaborate process with high pressures.

In the paper, however, we are talking about a localized conversion of regular aluminium metal into ‘transparent aluminium oxide’ under the influence of the anodization process. The electrowetting element simply means overcoming the surface tension of the liquid acid and does not otherwise matter. Effectively this process would create local spots of more aluminium oxide, which is… probably good for something?

Combined with the rather suspicious artefacts in the summary image raising so many red flags that rather than the ‘cool breakthrough’ folder we’ll be filing this one under ‘spat out by ChatGPT’ instead, not unlike a certain rat-centric paper that made the rounds about a year ago.

On February 13th of 2023, ARCA of the kilometre cubic neutrino telescope (KM3NeT) detected a neutrino with an estimated energy of about 220 PeV. This event, called KM3-230213A, is the most energetic neutrino ever observed. Although extremely abundant in the universe, neutrinos only weakly interact with matter and thus capturing such an event requires very large detectors. Details on this event were published in Nature.

Much like other types of telescopes, KM3NeT uses neutrinos to infer information about remote objects and events in the Universe, ranging from our Sun to other solar systems and galaxies. Due to the weak interaction of neutrinos they cannot be observed like photons, but only indirectly via e.g. photomultipliers that detect the blue-ish light of Cherenkov radiation when the neutrino interacts with a dense medium, such as the deep sea water in the case of ARCA (Astroparticle Research with Cosmics in the Abyss). This particular detector is located at a depth of 3,450 meters off the coast of Sicily with 700 meter tall detection units (DUs) placed 100 meters apart which consist out of many individual spheres filled with detectors and supporting equipment.

With just one of these high-power neutrinos detected it’s hard to say exactly where or what it originated from, but with each additional capture we’ll get a clearer picture. For a fairly new neutrino telescope project it’s also a promising start especially since the project as a whole is still under construction, with additional detectors being installed off the coasts of France and Greece.

What would it be like to have to design and build a ventilator, suitable for clinical use, in ten days? One that could be built entirely from locally-sourced parts, and kept oxygen waste to a minimum? This is the challenge [John Dingley] and many others faced at the start of COVID-19 pandemic when very little was known for certain.

Back then it was not even known if a vaccine was possible, or how bad it would ultimately get. But it was known that hospitalized patients could not breathe without a ventilator, and based on projections it was possible that the UK as a whole could need as many as 30,000 ventilators within eight weeks. In this worst-case scenario the only option would be to build them locally, and towards that end groups were approached to design and build a ventilator, suitable for clinical use, in just ten days.

[John] decided to create a documentary called Breathe For Me: Building Ventilators for a COVID Apocalypse, not just to tell the stories of his group and others, but also as a snapshot of what things were like at that time. In short it was challenging, exhausting, occasionally frustrating, but also rewarding to be able to actually deliver a workable solution.

In the end, building tens of thousands of ventilators locally wasn’t required. But [John] felt that the whole experience was a pretty unique situation and a remarkable engineering challenge for him, his team, and many others. He decided to do what he could to document it, a task he approached with a typical hacker spirit: by watching and reading tutorials on everything from conducting and filming interviews to how to use editing software before deciding to just roll up his sleeves and go for it.

We’re very glad he did, and the effort reminds us somewhat of the book IGNITION! which aimed to record a history of technical development that would otherwise have simply disappeared from living memory.

You can watch Breathe for Me just below the page break, and there’s additional information about the film if you’d like to know a bit more. And if you are thinking the name [John Dingley] sounds familiar, that’s probably because we have featured his work — mainly on self-balancing personal electric vehicles — quite a few times in the past.

Graphene always sounds exciting, although we aren’t sure what we want to do with it. One of the most promising features of the monolayer carbon structure is that under the right conditions, it can superconduct, and some research into how that works could have big impacts on practical superconductor technology.

Past experiments have shown that very cold stacks of graphene (two or three sheets) can superconduct if the sheets are at very particular angles, but no one really understands why. A researcher at Northeaster and another at Harvard realized they were both confused about the possible mechanism. Together, they have started progressing toward a better description of superconductivity in graphene.

Part of the problem has been that it is hard to make large pieces of multi-layer graphene. By creating two-ply pieces and using special techniques, an international team is finding that quantum geometry explains how graphene superconductors resist changes in current flow more readily than conventional superconductors.

Another team found that adding another layer makes the material behave more like a family of conventional higher-temperature superconductors. The research appears in two different papers. One covers the two-ply material. The other talks about the material with three layers.

Making little bits of graphene isn’t hard. Making it in quantity is a different story. We keep dreaming of what we could do with a room-temperature superconductor.

As great as silicon is for semiconductor applications, it has one weakness in that using it for lasers isn’t very practical. Never say never though, as it turns out that you can now grow lasers directly on the silicon material. The most optimal material for solid-state lasers in photonics is gallium-arsenide (GaAs), but due to the misalignment of the crystal lattice between the compound (group III-V) semiconductor and silicon (IV) generally separate dies would be produced and (very carefully) aligned or grafted onto the silicon die.

Naturally, it’s far easier and cheaper if a GaAs laser can be grown directly on the silicon die, which is what researchers from IMEC now have done (preprint). Using standard processes and materials, GaAs lasers were grown on industry-standard 300 mm silicon wafers. The trick was to accept the lattice mismatch and instead focus on confining the resulting flaws through a layer of silicon dioxide on top of the wafer. In this layer trenches are created (see top image), which means that when the GaAs is deposited it only contacts the Si inside these grooves, thus limiting the effect of the mismatch and confining it to within these trenches.

There are still a few issues to resolve before this technique can be prepared for mass-production, of course. The produced lasers work at 1,020 nm, which is a shorter wavelength than typically used, and there are still some durability issues due to the manufacturing process that have to be addressed.

Is fire conductive? As ridiculous that may sound at first glance, from a physics perspective the rapid oxidation process we call ‘fire’ produces a lot of substances that can reduce the electrical insulating (dielectric) properties of air. Is this change enough to allow for significant current to pass? To test this, [The Action Lab] on YouTube ran some experiments after being called out on this apparent fact in the comments to an earlier video.

Ultimately what you need to make ‘fire’ conductive is to have an appreciable amount of plasma to reduce the dielectric constant, which means that you cannot just use any rapid oxidation process. In the demonstration with lights and what appears to be a (relatively clean-burning) butane torch, the current conducted is not enough to light up an incandescent or LED light bulb, but can light up a 5 mm LED. When using his arm as a de-facto sensor, it does not conduct enough current to be noticeable.

The more interesting experiment here demonstrates the difference in dielectric breakdown of air at different temperatures. As the dielectric constant for hot air is much lower than for room temperature air, even a clean burning torch is enough to register on a multimeter. Ultimately this seems to be the biggest hazard with fire around exposed (HV) electrical systems, as the ionic density of most types of fire just isn’t high enough.

To reliably strike a conductive plasma arc, you’d need something like explosive (copper) wire and a few thousand joules to pump through it.

As the most important muscle in our body, any issues with our heart are considered critical and reason for replacement with a donor heart. Unfortunately donor hearts are rather rare, making alternatives absolutely necessary, or at the very least a way to coax the old heart along for longer. A new method here seems to be literally patching up a patient’s heart with healthy heart tissue, per the first human study results by [Ahmad-Fawad Jebran] et al. as published in Nature (as well as a partially paywalled accompanying article).

Currently, simple artificial hearts are a popular bridging method, which provide a patient with effectively a supporting pump. This new method is more refined, in that it uses induced pluripotent stem cells (iPS) from an existing hiPSC cell line (TC1133) which are then coaxed into forming cardiomyocytes and stromal cells, effectively engineered heart muscle (EHM). After first testing this procedure on rhesus macaque monkeys, a human trial was started involving a 46-year old woman with heart failure after a heart attack a few years prior.

During an operation in 2021, 10 patches of EHMs containing about 400 million cells each were grafted onto the failing heart. When this patient received a donor heart three months later, the removed old heart was examined and the newly grafted sections found to be healthy, including the development of blood vessels.

Although currently purely intended to be a way to keep people alive until they can get a donor heart, this research opens the tantalizing possibility of repairing a patient’s heart using their own cells, which would be significantly easier than growing (or bioprinting) an entire heart from scratch, while providing the benefit of such tissue patches grown from one’s own iPS cells not evoking an immune response and thus mitigating the need for life-long immune system suppressant drugs.

Featured image: Explanted heart obtained 3 months after EHM implantation, showing the healthy grafts. (Credit: Jebran et al., 2025, Nature)

Transition-metal dichalcogenides (TMDs) are the subject of an emerging field in semiconductor research, with these materials offering a range of useful properties that include not only semiconductor applications, but also in superconducting material research and in supercapacitors. A recent number of papers have been published on these latter two applications, with [Rui] et al. demonstrating superconductivity in (InSe₂)_xNbSe₂. The superconducting transition occurred at 11.6 K with ambient pressure.

Two review papers on transition metal sulfide TMDs as supercapacitor electrodes were also recently published by [Mohammad Shariq] et al. and [Can Zhang] et al. showing it to be a highly promising material owing to strong redox properties. As usual there are plenty of challenges to bring something like TMDs from the laboratory to a production line, but TMDs (really TMD monolayers) have already seen structures like field effect transistors (FETs) made with them, and used in sensing applications.

TMDs consist of a transition-metal (M, e.g. molybdenum, tungsten) and a chalcogen atom (X, e.g. sulfur) in a monolayer with two X atoms (yellow in the above image) encapsulating a single M atom (black). Much like with other monolayers like graphene, molybdenene and goldene, it is this configuration that gives rise to unexpected properties. In the case of TMDs, some have a direct band gap, making them very suitable for transistors and perhaps most interestingly also for directly growing 3D semiconductor structures.

Heading image: Crystal structure of a monolayer of transition metal dichalcogenide.(Credit: 3113Ian, Wikimedia)

Have you ever struggled with the concept of quantum measurement, feeling it’s unnecessarily abstract? You’re not alone. Enter this guide by [Mithuna] from Looking Glass Universe, where she circles back on the concept of  measurement basis in quantum mechanics using a rather simple piece of calcite crystal. We wrote about similar endeavours in reflection on Shanni Prutchi’s talk at the Hackaday SuperConference in 2015. If that memory got a bit dusty in your mind, here’s a quick course to make things click again.

In essence, calcite splits a beam of light into two dots based on polarization. By aligning filters and rotating angles, you can observe how light behaves when forced into ‘choices’. The dots you see are a direct representation of the light’s polarization states. Now this isn’t just a neat trick for photons; it’s a practical window into the probability-driven nature of quantum systems.

Even with just one photon passing through per second, the calcite setup demonstrates how light ‘chooses’ a path, revealing the probabilistic essence of quantum mechanics. Using common materials (laser pointers, polarizing filters, and calcite), anyone can reproduce this experiment at home.

If this sparks curiosity, explore Hackaday’s archives for quantum mechanics. Or just find yourself a good slice of calcite online, steal the laser pointer from your cat’s toy bin, and get going!

In lieu of high-explosives, an exploding wire circuit can make for an interesting substitute. As [Hyperspace Pirate] demonstrates in a recent video, the act of pumping a lot of current very fast through a thin piece of metal can make for a rather violent detonation. The basic idea is that by having the metal wire (or equivalent) being subjected to a sufficiently large amount of power, it will not just burn through, but effectively vaporize, creating a very localized stream of plasma for the current to keep travelling through and create a major shockwave in the process.

This makes the exploding wire method (EWM) an ideal circuit for any application where you need to have a very fast, very precise generating of plasma and an easy to synchronize detonation. EWM was first demonstrated in the 18th century in the Netherlands by [Martin van Marum]. These days it finds use for creating metal nanoparticles, brief momentary light sources and detonators in explosives, including for nuclear (implosion type) weapons.

While it sounds easy enough to just strap a honkin’ big battery of capacitors to a switch and a piece of wire, [Hyperspace Pirate]’s video demonstrates that it’s a bit more involved than that. Switching so much current at high voltages ended up destroying a solid-state (SCR) switch, and factors like resistance and capacitance can turn an exploding wire into merely a heated one that breaks before any plasma or arcing can take place, or waste a lot of potential energy.

As for whether it’s ‘try at home’ safe, note that he had to move to an abandoned industrial site due to the noise levels, and the resulting machine he cobbled together involves a lot of high-voltage wiring. Hearing protection and extreme caution are more than warranted.

Of course there is bone-simulation filament on the market. What’s fun about this Reddit thread is all of the semi-macabre concerns of surgeons who are worried about its properties matching the real thing to make practice rigs for difficult surgeries. We were initially creeped out by the idea, but now that we think about it, it’s entirely reassuring that surgeons have the best tools available for them to prepare, so why not 3D prints of the actual patient’s bones?

[PectusSurgeon] says that the important characteristics were that it doesn’t melt under the bone saw and is mechanically similar, but also that it looks right under x-ray, for fluorscopic surgery training. But at $100 per spool, you would be forgiven for looking around for substitutes. [ghostofwinter88] chimes in saying that their lab used a high-wood-content PLA, but couldn’t say much more, and then got into a discussion of how different bones feel under the saw, before concluding that they eventually chose resin.

Of course, Reddit being Reddit, the best part of the thread is the bad jokes. “Plastic surgery” and “my insurance wouldn’t cover gyroid infill” and so on. We won’t spoil it all for you, so enjoy.

When we first read “printing bones”, we didn’t know if they were discussing making replacement bones, or printing using actual bones in the mix. (Of course we’ve covered both before. This is Hackaday.)

Thanks [JohnU] for the tip!

It’s a well-known fact that anti-ferromagnetic materials are called that way because they cannot be magnetized, not even in the presence of a very strong external magnetic field. The randomized spin state is also linked with any vibrations (phonons) of the material, ensuring that there’s a very strong resistance to perturbations. Even so, it might be possible to at least briefly magnetize small areas through the use of THz-range lasers, as they disrupt the phonon-spin balance sufficiently to cause a number of atoms to ‘flip’, resulting in a localized magnetic structure.

The research by [Baatyr Ilyas] and colleagues was published in Nature, describing the way the 4.8 THz pulses managed to achieve this feat in FePS₃ anti-ferromagnetic material. The change in spin was verified afterwards using differently polarized laser pulses, confirming that the local structures remained intact for at least 2.5 milliseconds, confirming the concept of using an external pulse to induce phonon excitation. Additional details can be found in the supplemental information PDF for the (sadly paywalled with no ArXiv version) paper.

As promising as this sounds, the FePS₃ sample had to be cooled to 118K and kept in a vacuum chamber. The brief magnetization also doesn’t offer any immediate applications, but as a proof of concept it succinctly demonstrates the possibility of using anti-ferromagnetic materials for magnetic storage. Major benefit if such storage can be made more permanent is that it might be more stable and less susceptible to outside influences than traditional magnetic storage. Whether it can be brought out of the PoC stage into at least a viable prototype remains to be seen.

Every engineer is going to have a bad day, but only an unlucky few will have a day so bad that it registers on a seismometer.

We’ve always had a morbid fascination with engineering mega-failures, few of which escape our attention. But we’d never heard of the Super-Kamiokande neutrino detector implosion until stumbling upon [Alexander the OK]’s video of the 2001 event. The first half of the video below describes neutrinos in some detail and the engineering problems related to detecting and studying a particle so elusive that it can pass through the entire planet without hitting anything. The Super-Kamiokande detector was built to solve that problem, courtesy of an enormous tank of ultrapure water buried 1,000 meters inside a mountain in Japan and lined with over 10,000 supersized photomultiplier tubes to detect the faint pulses of Chernkov radiation emitted on the rare occasion that a neutrino interacts with a water molecule.

Those enormous PM tubes would be the trigger for the sudden demise of the Super-K , which is covered in the second half of the video. During operations to refill the observatory after routine maintenance, technicians noticed a bang followed by a crescendo of noise from the thirteen-story-tall tank. They quickly powered down the system and took a look inside the tank to find almost every PM tube destroyed. The resulting investigation revealed that the tubes had failed in sequence following the sudden implosion of a single tube at the bottom of the tank. That implosion caused a shock wave to propagate through the water to surrounding tubes which exceeded their design limits, causing further implosions and further destruction. The cascading implosion took a full ten seconds to finish its wave of destruction, which destroyed $7 million worth of tubes.

The interesting part about this is the root cause analysis, which boils down to the fact that you shouldn’t stand on 50-cm photomultiplier tubes. Also at fault was the testing regimen for the tubes, which the project engineers anticipated could cause a cascading implosion. They tested this but were unable to cause a cascade failure, leading them to the conclusion it wasn’t likely to happen. But analysis of the destruction revealed a flaw in the testing, which should give pause to anyone who ever had to design a test like this before.

Luckily, nobody was killed or even hurt during the Super-K incident. The observatory was repaired with upgraded tubes and remains in service to this day, with an even bigger Hyper-Kamiokande detector in the works. We’ve covered neutrino observatories before, so check that out if you want more background on the science.

Imagine a clock where the colors aren’t from LEDs but a physics phenomenon – polarization. That’s just what [Mosivers], a physicist and electronics enthusiast, has done with the Polarizer Clock. It’s not a perfect build, but the concept is intriguing: using polarized light and stress-induced birefringence to generate colors without resorting to RGB LEDs.

The clock uses white LEDs to edge-illuminate a polycarbonate plate. This light passes through two polarizers—one fixed, one rotating—creating constantly shifting colours. Sounds fancy, but the process involves more trial and error than you’d think. [Mosivers] initially wanted to use polarizer-cut numbers but found the contrast was too weak. He experimented with materials like Tesa tape and cellophane, choosing polycarbonate for its stress birefringence.

The final design relies on a mix of materials, including book wrapping foil and 3D printed parts, to make things work. It has its quirks, but it’s certainly clever. For instance, the light dims towards the center, and the second polarizer is delicate and finicky to attach.

This gadget is a splendid blend of art and science, and you can see it in the video below the break. If you’re inspired, you might want to look up polariscope projects, or other birefringence hacks on Hackaday.