The farther you get from the equator, the less effective solar panels become at reliably generating power all year round. And it’s not just the shorter spans of sunlight during the winter months that are a problem; even a light dusting of snow can render solar panels ineffective. As a result of global warming, winters are only going to get more severe, but there’s at least one silver lining as researchers from UCLA have come up with a way to harness electricity from all that snow.
The technology they developed is called a snow-based triboelectric nanogenerator (or snow TENG, for short) which generates energy from the exchange of electrons. If you’ve ever received a nasty shock when touching a metal door handle, you’ve already experienced the science at work here. As it falls towards earth, snowflakes are positively charged and ready to give up electrons. In a way, it’s almost free energy ready for the taking, so after testing countless materials with an opposite charge, the UCLA researchers (working with collaborators from the University of Toronto, McMaster University, and the University of Connecticut) found that the negative charge of silicone made it most effective for harvesting electrons when it came into contact with snowflakes.
Details about the device they created were shared in a paper published in the Nano Energy journal, but it can be 3D-printed on the cheap given how accessible silicone is—for five bucks you can buy a spray can of it at the hardware store as a lubricant. In addition to silicone, a non-metal electrode is used, which results in the triboelectric generator being flexible, stretchable, and extremely durable.
Its creators believe it could be integrated into solar panel arrays so that when blanketed with snow in the winter months, they could continue to generate power. But the triboelectric generator has other potential uses too. Since it doesn’t require batteries or charging, it could be used to create cheap, self-powered weather stations that could report back snowy conditions and how much has accumulated. It could also improve activity trackers used by athletes competing in winter sports, allowing the movements of individual skis to be tracked and recorded which would provide valuable insights for athletes as they train to perfect their form.
It just became decidedly easier to use your Android phone to board a flight or see a movie. Google Pay is rolling out a server-based update that lets the app automatically fetch boarding passes, tickets and loyalty cards from Gmail. You’ll have to enable it yourself (it’s under Settings > General > Gmail Imports), but this could save a lot of time if you’re tired of sifting through messages to find a ticket at the theater.
Don’t be surprised if the feature isn’t available yet on your phone. It was when we tried it, but Google’s rollouts can take days or weeks. The company also cautions that deleting the root email messages will also eliminate the Google Pay entries, so this isn’t quite like Apple’s Wallet (where tickets are separate items). If you can live with those quirks, though, this could give you a good reason to rely on Google Pay instead of digging through Gmail yourself.
The idea to launch billboards into space may have seemed like just another marketing gimmick. Back in January, Discover first reported on a Russian start-up company named StartRocket that said it wanted to use swarms of mini satellites called CubeSats to project ads on the night sky from low-Earth orbit. Readers reacted harshly to the announcement. Some called it “repulsive.” Others urged boycotts of any company that took them up on the offer.
But the beverage giant PepsiCo actually took
are real! The LAZARETH LMV 496 is part motorcycle part flying machine. LAZARETH LMV 496 is a 4-wheeled flying concept. Created by designer and engineer Ludovic Lazareth. On the road, the LMV 496 has 62 miles of all-electric range, and with the flip of a switch LMV 496 transitions into a flying machine. The LMV 496 has a 10 minute flight time. During transformation, the tires rotate creating 4 downward-facing turbines. The turbines create 1,300 horsepower and 630 pounds of force. Speed, altitude, position, and turbine speed can all be read on the dashboard. There’s no word on pricing yet but we bet it won’t be cheap.
The Stratolaunch is the world’s largest plane by wingspan. During its first test flight on Saturday, the plane reached an altitude of 17,000 feet and a speed of 189 mph.
Laser beams illuminating unit of Diode Pumped Green Laser.
Forrest Anderson | The LIFE Images Collection | Getty Images
The data usage of the modern world is absolutely mind-boggling. We have giant, air-conditioned buildings dedicated to shuffling bits around at high speed. And for what? To ensure that Instagram can tell Facebook to tell its advertisers that you really love rubber duckies.
Vicious truth-telling aside, the infrastructure underlying data centers is based on lasers that are modulated at high speed. Thanks to some recently published research, however, the latest and greatest of the hardware currently in our data centers will start to look very slow. A speed-up of about a factor of 10 may be just around the corner.
Birefringence is your friend
It turns out that the key to making a laser go faster is to make it a bit shoddy. Let’s break that down.
To transfer information, it’s common to modulate the brightness of the laser light. For a laser diode, this is done by varying the electrical current supplied to the diode. But it doesn’t matter how quickly you can vary the current; the laser will respond in its own sweet time. Overcoming that limitation traditionally involves turning the power up, but this new approach avoids that requirement.
To understand this idea, we need to review several concepts. So buckle up and prepare to ride Chris’ concept rollercoaster.
The lasers in telecommunications are made from semiconductor crystals. The speed at which light travels through a material is modified by the material’s refractive index. Air has a refractive index that is just a whisker over one. Glass is about 1.3, and semiconductors are typically around three to four. That means the speed of light slows down by a factor of three to four, while the wavelength contracts by the same factor.
However, crystals are not perfect. They often have strain that distorts the crystal structure. This means that an electric field along one direction will experience a slightly different refractive index compared to an electric field that is rotated 90 degrees. And photons have electric fields.
Imagine two photons traveling together through our strained semiconductor. One has its electric field oriented horizontally, and the other vertically. They start out perfectly synchronized with each other, but after a short distance they are no longer in sync because one photon is traveling slightly slower than the other. From the perspective of a viewer looking down the barrel of the photon gun, the electric field appears to trace out an ellipse.
If we pass a stream of photons through a polarization filter, which blocks certain orientations, the intensity of the output beam will fluctuate as the electric field traces this ellipse. The rate of fluctuation—how quickly the ellipse gets traced—depends on the difference in refractive index for horizontal and vertically polarized photons (called birefringence). The bigger the difference, the faster the fluctuations.
This has been known for a long time and is generally considered an annoyance. But remember, fluctuations in brightness can be used to carry data; the question here is whether we can turn this annoyance into something useful.
Electrons have polarization, too
To use this system to carry information, we need to control the rotation of the ellipse. That means controlling the number of photons in each polarization.
The polarization of light that is emitted by an electron in a laser diode is given by the change in spin as the electron loses energy. So an electron enters the diode spin up, emits a photon, loses energy, and flips to spin down. Likewise, a photon that enters the diode spin down will emit a photon, lose energy, and flip to spin up. The balance between spin-up and spin-down electrons determines the polarization of the emitted light.
To encode information, the balance between spin-up and spin-down electrons that enter the laser diode should change: say from 75:25 for a logical one to 25:75 for a logical zero. The resulting light polarization would fluctuate as fast as we can switch between these two balance of spins in the electron current to the laser diode.
Therein lies the next problem. The electrons don’t immediately lose their energy. Instead, many of them hang around awaiting inspiration before doing so. These tardy electrons smear out the sharp modulation that we put into the laser, and this limits the data transfer rate to speeds that we can already achieve with current technology. Hence, we might put in a stream of electrons that are all spin up. A few of them emit immediately, but the rest first bounce around losing their spin orientation before they emit. The result is a background of light that contains no information, and, on top of that, weak flashes that carry information.
To get higher speeds and clear signals, we need to force the electrons to lose their spin orientation very quickly. This happens naturally when the electrons bounce off the imperfections in the crystal.
The need for speed
To get things to flip spin quickly, the researchers used a laser diode that was… a bit poor. The time that a spin-polarized current would stay polarized was really small, meaning that spin flips happen quickly. The researchers attached the laser diode to a cantilever and bent the cantilever. That stressed the laser diode along one direction, changing its refractive index drastically.
The researchers showed that they could drive intensity oscillations at up to 200GHz, which is an order of magnitude better than previous results.
Sending information is another story, though; the researchers couldn’t directly test that. Instead, they used their experimental data to model the laser. With that model, they could see how changing the spin orientation of the injected electrons would change the output of the laser. They showed that for modulation speeds up to 200GHz, information was encoded—in the words of telecommunications engineers everywhere, the eyes were open.
This research will revolutionize short-distance network traffic. Not only do data rates go up, but energy per bit goes down by over an order of magnitude. There is, however, a small issue. At the moment, I don’t think there is a single device on the planet that can modulate the spin orientation of an electric current at 200GHz. Photodetectors at the receiver may also need some attention. But those developments are only a matter of time once the underlying technology is available.
I’m all for big TVs, the bigger the screen, the better. In fact, given the space and inclination, I’d go all-in on a projector instead of a TV. Sony has a new UHD TV that is the biggest we’ve ever seen. The giant MicroLED display is 17-feet high and 63-feet long.
That is about the size of a bus. I want to play Red Dead Redemption 2 on it. The tech inside the TV is called Crystal LED, and it has 16k screen resolution. That’s a lot.
That resolution gives 16 times the pixels you will find in a typical 4K UHD display. The giant screen isn’t a single massive screen; rather it is a bunch of bezel-free panels put together.
From a distance in photos, you can’t tell there are seams, but it’s not clear if you can tell up close. Screens like this are expected to replace the projector and silver screen at movie theaters one day reports Maxim.
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