Nano-switches made out of graphene could make our electronics even smaller

For the first time, physicists have built reliable, efficient graphene nanomachines that can be fabricated on silicon chips. They could lead to even greater miniaturization.

The chances are that you own a microelectromechanical device—probably dozens of them. These devices fill the modern world. They make possible the accelerometers in smartphones, the microphones in laptops, and the micromirrors in digital projectors, to name just a few.

They are typically a few micrometers in size, tiny by any standards. But scientists and engineers want them even smaller—on the nanometer scale, if possible. At that size, these machines can work as simple switches in logic and memory devices, raising the prospect of more powerful and more efficient data-processing devices.

These micromachines are generally carved into silicon chips. But as they get smaller, silicon switches become less efficient because they leak current when they are off. A better option is a graphene switch, which is easy to carve on a nanometer scale and relatively straightforward to build into conventional silicon chips. Neither does it leak current when it is off.

But there is a problem. When graphene touches silicon, it tends to stick fast. Imagine a switch consisting of a flexible graphene bar that forms a circuit when the bar touches a silicon electrode. If the bar sticks to the electrode, it cannot be switched off again.

This problem is known as stiction. And despite significant financial investment in graphene research by governments all over the world, nobody has found a good way to solve it.

Enter Kulothungan Jothiramalingam at the Japan Advanced Institute of Science and Technology and colleagues, who have found a solution. Using it, they have created graphene-based nanoelectromechanical devices that can act as switches and even as logic gates.

Their method is straightforward. They coat a silicon chip with nanocrystalline graphene, which sticks fast to the surface. Then they cover this with a layer of hydrogen silsesquioxane, which acts as a resist and can be carved into various shapes. On top of this they place another layer of graphene.

The trick is to carve the top layer of graphene into a bar shape that is anchored at both ends by electrodes. Then they remove the hydrogen silsesquioxane layer underneath part of the graphene bar to leave it suspended above the graphene layer.

Bending this bar is simple. A potential difference between the layers creates a force that bends the bar to toward the chip. When it touches this lower surface, it forms a circuit, a process that can be exploited for logic and for data storage.

That’s the switch. And because the two surfaces that come into contact are both graphene, there is no stiction. Switching off the potential difference releases the bar, which springs back into its original position.

Jothiramalingam and co used this approach to build a variety of proof-of-principle nano-switches, including single switches and an array. They say the devices work well with low voltages of just 1.5 volts and that in the off state, there is very little current leakage because the graphene bars are well insulated from other conducting layers.

There are some challenges, though. For example, the shape and size of the graphene beam and its distance from the lower layer need to be optimized to achieve reliable switching. But this should be a straightforward engineering problem.

Once that is solved, more complex devices become possible. The team has designed a range of more complex switches including an AND logic gate and a three-terminal switch in which they place three layers of graphene on top of each other, separated by an insulating layer of hydrogen silsesquioxane.

That’s interesting work with the potential to make nanoelectromechanical devices even smaller, based on the promise of the wonder material that is graphene.

Ref: arxiv.org/abs/1901.07754 : Stacking of Nanocrystalline Graphene for Nano-ElectroMechanical (NEM) Actuator Applications


Source
Author: Emerging Technology from the arXiv
Image Credit

 

Bitrefill adds Amazon voucher purchase on their portfolio

The company who pioneers prepaid mobile phones top up in over 160 countries using cryptocurrencies, Bitrefill has brought Amazon into their portfolio, by enabling Amazon voucher purchase using Bitcoin and other cryptocurrencies.

Bitrefill, the company who pioneers prepaid mobile phones top up in over 160 countries using cryptocurrencies, just announced their newest service in a blog post. The company now offers their users the availability to purchase Amazon vouchers using Bitcoin and other supported cryptocurrencies on their platform.

According to their announcement, Bitrefill’s users have been asking for more vouchers to be added on the platform, with Amazon’s became the most requested. With the service now being added, users can purchase Amazon’s vouchers using Bitcoin or several other cryptocurrencies, such as LTC, ETH, DOGE, and DASH in a pretty straightforward process.

As one of the early adopters of the Lightning Network payment protocol, the company offers the second layer protocol as one of the payment options on their platform. And despite the technical problems the new payment protocol have, Bitrefill’s CEO, Sergej Kotliar, is still very hopeful and believes in its future.

As he said in an interview with Bitcoinist, “Lightning will be a way of future-proofing Bitcoin, to know that we will be able to do fast and cheap transactions for a long time forwards.”

Aside from Amazon, Bitrefill just added Uber and Hotels.com vouchers to their platform earlier last month.


Here at Dollar Destruction, we endeavour to bring to you the latest, most important news from around the globe. We scan the web looking for the most valuable content and dish it right up for you! The content of this article was provided by the source referenced. Dollar Destruction does not endorse and is not responsible for or liable for any content, accuracy, quality, advertising, products or other materials on this page. As always, we encourage you to perform your own research!

Source
Author: Fifi Arisandi
Image Credit

Don’t forget to join our facebook page for Crypto, Business & Technology news delivered to you daily.

Google Pixel phones will automatically send spam calls to voicemail

Google Pixel phones will automatically send spam calls to voicemail!

Spam calls are universally terrible, and Google is taking steps to help you ignore them by automatically sending spam calls to voicemail instead of letting them ring, as spotted via 9to5Google.

The Google Phone app already flags spam numbers and lights up the screen bright red when one comes in (as seen in the image above), but the new spam filtering goes a step further, sending robocalls straight to voicemail without even bothering you with a missed call notification.

Of course, this requires Google to accurately identify spam calls, which is a constant cat and mouse game between spammers and the software company. But if it even stops a few spam calls from interrupting your day, it’ll already be a big improvement.

The new feature should be rolling out worldwide over the next few weeks in Google’s default Phone app on Android. If you have a Pixel, Nexus, or Android One device, you already have the feature on your phone. Other Android users can install it manually through the Play Store.


Here at Dollar Destruction, we endeavour to bring to you the latest, most important news from around the globe. We scan the web looking for the most valuable content and dish it right up for you! The content of this article was provided by the source referenced. Dollar Destruction does not endorse and is not responsible for or liable for any content, accuracy, quality, advertising, products or other materials on this page. As always, we encourage you to perform your own research!

Source
Author: Chaim Gartenberg
Image Credit

 

Huawei’s P20 Pro rivals the best smartphone cameras out there

Some of its top features are hidden away, but the results speak for themselves.

We’re a sceptical bunch here and when Huawei briefed the world on its P20 Pro smartphone, listing an endless torrent of specifications and dubbing its Leica Triple Camera system “the most advanced camera on a phone yet,” we collectively rolled our eyes. Forty-megapixel camera sensor? I’ve heard that one before, Huawei.

It was only once I was able to test the P20 Pro away from briefing rooms and technical demos (spending a day shooting around a rain-soaked Paris) that the phone started to win me over — and others. If you like the idea of an accomplished 5x zoom function, and the potential for gorgeous night time photography, you have to consider Huawei’s latest phones.

First, let’s summarize some of the major camera specs. All the fun is centred around the “Leica Triple Camera.” That includes an 8-megapixel telephoto shooter with an f/2.4 lens and optical image stabilization and a 40-megapixel camera with an f/1.8 lens.

Oh, and there’s an extra 20-megapixel monochrome sensor (with f/1.6 lens) and a colour temperature sensor for accurate white balance. If you needed one more lens, don’t worry: There’s a 24-megapixel front-facing camera too.

AI camera

Beside all the hardware numbers, Huawei’s sales pitch on imaging centres on the AI smarts that come alongside the P20’s camera spec sheet, and the standard still photography mode has AI assistance turned on automatically. (You can turn it off in settings.)

However, coaxing the temperamental AI feature to make an appearance was rage-inducing — especially when you’re looking to test whether it’s identifying objects correctly and how it decides to adjust settings when it spots something that warrants it … like in a camera test. Is this better than misjudged scene modes, like we saw with LG’s similarly AI-skilled V30 ThinQ? I’m not sure — I just wanted more consistency.

Temperamental behaviour wasn’t a deal-breaker, however, simply because I was so pleased with the photos that the AI-assisted camera eventually did capture. They are all Instagram-ready right out of the box: portrait-mode-detected images had smoother skin tone and added gently blurred backgrounds, while the P20 Pro boosted the colours it picked out on food and flower shots.

Huawei’s imaging algorithms and settings, while a little aggressive with saturation and bokeh effects, sometimes employed only a light touch to photos. Here’s the P20 Pro’s AI setting for food photography, compared with a standard shot on the iPhone X.

If anything, Apple’s phone amps up the colour on the strawberries a little too far. Note how the white sign stays white in the P20 Pro sample. Huawei installed a colour temperature sensor amid all those camera lenses, and it seems to do a pretty good job.

Hybrid zoom

Huawei’s zoom system works so much better than I thought it would. The P20 Pro uses both the telephoto camera lens — capable of 3x optical zoom — and the 40MP primary sensor to offer a hybrid 5x zoom that takes really, really impressive stills.

Interestingly, 3x zoom on the telephoto lens alone would be enough to best the iPhone or the Galaxy series, both of which go with 2x optical zoom. The hybrid option then adds a substantially bigger jump in magnification, which made framing easier and ensured I got all the detail I wanted in my shots. I’d normally shy away from digital zoom, because it usually makes muddier, noisier images. The P20 Pro’s hybrid zoom didn’t have that issue.
Night time shooting was another situation where the P20 Pro shone. As I mentioned in passing during my preview, the phone comes with long-exposure modes that don’t require tripods. From what I’ve been told, it combines the Kirin NPU chip to chew over long-exposure captures and bring them all together, with the high-megapixel primary shooter doing a lot of the legwork.

The results were often jaw-dropping: When in Paris, right?

In comparison, taking the same shots on my iPhone X resulted in noisy, hazy photos. Pretty, but simply not as good. Meanwhile, look at the detail on the Eiffel Tower’s cross-struts above: It’s impressive as heck. (I’ve included all my full-size images in a Flickr album below.) Better still, it was easy. No tripod; swiped to “Night mode” in the camera app; tapped on la tour Eiffel; and this was the result. In low light elsewhere, the P20 Pro also delivered reliable photos that were nicely contrasted, with plenty of detail.

Finding the right mode for great photos

There’s a handful of other tricks and modes that you have to actively seek out, and that’s the biggest problem when it comes to Huawei’s otherwise wonderful camera phone. It’s hard to find the settings that you’re looking for. The company says the P20 can reach an ISO setting of up to 102,400 — that would be as much as many DSLRs, but I couldn’t test it, because it’s coming in a later software update. It also took me a while to figure out long-exposure settings too. My tip? Just select Night mode. It’s easier.

I enjoyed unearthing the P20 Pro’s range of shooting tricks (monochrome photography, aperture mode for post-shooting focus, portrait mode, light painting and many more) and useful features that goes beyond image quality: the fact that the P20 Pro can boot into the camera app and snap a (out-of-focus) still immediately in less than 0.3 seconds.

Those interface issues shouldn’t detract too much from the miraculous photos this phone is capable of taking. The main question is: How patient are you? You really have to pin down the shooting options that work for you, whether that means turning the AI assistant off entirely or sticking to the Pro mode.

Yes, it takes time to learn the ropes on Huawei’s P20 Pro, but the results prove it’s worth it.


 

Here at Dollar Destruction, we endeavour to bring to you the latest, most important news from around the globe. We scan the web looking for the most valuable content and dish it right up for you! The content of this article was provided by the source referenced. Dollar Destruction does not endorse and is not responsible for or liable for any content, accuracy, quality, advertising, products or other materials on this page. As always, we encourage you to perform your own research!

Source

Author Mat Smith

Image credit