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Light is notoriously fast. Its speed is crucial for rapid information exchange, but as light zips through materials, its chances of interacting and exciting atoms and molecules can become very small. If scientists can put the brakes on light particles, or photons, it would open the door to a host of new technology applications.

Now, in a paper published in Nature Nanotechnology, Stanford scientists demonstrate a new approach to slow light significantly, much like an echo chamber holds onto sound, and to direct it at will. Researchers in the lab of Jennifer Dionne, associate professor of materials science and engineering at Stanford, structured ultrathin silicon chips into nanoscale bars to resonantly trap light and then release or redirect it later. These “high-quality-factor” or “high-Q” resonators could lead to novel ways of manipulating and using light, including new applications for quantum computing, virtual reality and augmented reality; light-based WiFi; and even the detection of viruses like SARS-CoV-2.

Stanford scientists slow and steer light with resonant nanoantennas

An artist rendering of a high-Q metasurface beamsplitter. These “high-quality-factor” or “high-Q” resonators could lead to novel ways of manipulating and using light. Image credit: Riley A. Suhar

“We’re essentially trying to trap light in a tiny box that still allows the light to come and go from many different directions,” said postdoctoral fellow Mark Lawrence, who is also lead author of the paper. “It’s easy to trap light in a box with many sides, but not so easy if the sides are transparent – as is the case with many Silicon-based applications.”

Make and manufacture

Before they can manipulate light, the resonators need to be fabricated, and that poses a number of challenges.

A central component of the device is an extremely thin layer of silicon, which traps light very efficiently and has low absorption in the near-infrared, the spectrum of light the scientists want to control. The silicon rests atop a wafer of transparent material (sapphire, in this case) into which the researchers direct an electron microscope “pen” to etch their nanoantenna pattern. The pattern must be drawn as smoothly as possible, as these antennas serve as the walls in the echo-chamber analogy, and imperfections inhibit the light-trapping ability.

“High-Q resonances require the creation of extremely smooth sidewalls that don’t allow the light to leak out,” said Dionne, who is also Senior Associate Vice Provost of Research Platforms/Shared Facilities. “That can be achieved fairly routinely with larger micron-scale structures, but is very challenging with nanostructures which scatter light more.”

Pattern design plays a key role in creating the high-Q nanostructures. “On a computer, I can draw ultra-smooth lines and blocks of any given geometry, but the fabrication is limited,” said Lawrence. “Ultimately, we had to find a design that gave good-light trapping performance but was within the realm of existing fabrication methods.”

High quality (factor) applications

Tinkering with the design has resulted in what Dionne and Lawrence describe as an important platform technology with numerous practical applications.

The devices demonstrated so-called quality factors up to 2,500, which is two orders of magnitude (or 100 times) higher than any similar devices have previously achieved. Quality factors are a measure describing resonance behavior, which in this case is proportional to the lifetime of the light. “By achieving quality factors in the thousands, we’re already in a nice sweet spot from some very exciting technological applications,” said Dionne.

For example, biosensing. A single biomolecule is so small that it is essentially invisible. But passing light over a molecule hundreds or thousands of times can greatly increase the chance of creating a detectable scattering effect.

Dionne’s lab is working on applying this technique to detecting COVID-19 antigens – molecules that trigger an immune response – and antibodies – proteins produced by the immune system in response. “Our technology would give an optical readout like the doctors and clinicians are used to seeing,” said Dionne. “But we have the opportunity to detect a single virus or very low concentrations of a multitude of antibodies owing to the strong light-molecule interactions.” The design of the high-Q nanoresonators also allows each antenna to operate independently to detect different types of antibodies simultaneously.

Though the pandemic spurred her interest in viral detection, Dionne is also excited about other applications, such as LIDAR – or Light Detection and Ranging, which is laser-based distance measuring technology often used in self-driving vehicles – that this new technology could contribute to. “A few years ago I couldn’t have imagined the immense application spaces that this work would touch upon,” said Dionne. “For me, this project has reinforced the importance of fundamental research – you can’t always predict where fundamental science is going to go or what it’s going to lead to, but it can provide critical solutions for future challenges.”

This innovation could also be useful in quantum science. For example, splitting photons to create entangled photons that remain connected on a quantum level even when far apart would typically require large tabletop optical experiments with big expensive precisely polished crystals. “If we can do that, but use our nanostructures to control and shape that entangled light, maybe one day we will have an entanglement generator that you can hold in your hand,” Lawrence said. “With our results, we are excited to look at the new science that’s achievable now, but also trying to push the limits of what’s possible.”

Source: Stanford University




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Micromax in 1b to Go on Sale in India for First Time Today via Flipkart, Company Site: Price, Specifications

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Micromax In 1b is all set to go on sale in India today. The phone comes with an octa-core MediaTek Helio G35 SoC and features a 6.52-inch full-HD+ display. It also comes with a dual rear camera setup that houses a 13-megapixel primary sensor. The Micromax In 1b also has an 8-megapixel selfie camera sensor inside the waterdrop-style notch. The company has integrated a 5,000mAh battery inside the In 1b that supports reverse charging and 10W fast charging.

Micromax In 1b price in India, sale

The Micromax In 1b will go on sale at 12pm (noon) on Flipkart and Micromax.com. The phone is priced at Rs. 6,999 for the 2GB RAM + 32GB storage option and at Rs. 7,999 for the 4GB RAM + 64GB storage model. Micromax In 1b will be available in Green, Blue, and Purple colour options.

Flipkart offers include 5 percent cashback on Flipkart Axis Bank credit card, 5 percent off with Axis Bank Buzz credit card, and no-cost EMI starting from Rs. 778 per month.

Micromax In 1b specifications

Coming to specifications, the Micromax In 1b runs on Android 10 and features a 6.52-inch HD+ display. It is powered by an octa-core MediaTek Helio G35 SoC, paired with up to 4GB of RAM options. On the storage front, the Micromax In 1b carries up to 64GB of onboard storage options that are expandable via microSD card.

As for imaging, the Micromax In 1b offers a dual rear camera setup that houses a 13-megapixel primary camera sensor and a 2-megapixel depth sensor, along with an LED flash. The Micromax phone also comes with an 8-megapixel selfie camera sensor at the front.

Micromax In 1b comes with a 5,000mAh battery that supports reverse charging and 10W fast charging (compatible charger is bundled in the box). Connectivity options include 4G VoLTE, Wi-Fi, Bluetooth, GPS/ A-GPS, USB Type-C, and a 3.5mm headphone jack. The phone also features a fingerprint sensor at the back.

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AI automation promises to have a big, and not always positive, impact

robots working 5

Commentary: Just as telephone operators struggled with the automation of switching, AI promises to change global economies for the better, even as it wreaks havoc on individuals’ jobs.

Image: iStockphoto/PhonlamaiPhoto

The robots may not be taking over, but they just might erase your job. Yes, it’s almost certainly true that the “creative destruction” of technology will result in more jobs than it destroys, but a new academic paper about US telephone operators displaced by automated switching suggests that while the overall economy will be better off with artificial intelligence (AI)-driven automation, those immediately impacted may never recover. 

Better in the long run

As detailed recently by Daphne Leprince-Ringuet on sister site ZDNet, the World Economic Forum (WEF) expects to see AI and other new technologies shred 85 million jobs over the next five years–that’s the bad news. The good news is that these same technologies are expected to help create 97 million new jobs. COVID-19 has served as an accelerant to corporate plans to embrace things like AI/ML-driven automation, effectively hitting “fast forward” on this labor upheaval. All of this is for the better, at least at the macro level.

SEE: The new normal: What work will look like post-pandemic (TechRepublic Premium)

In practical terms, this means that the majority of the work associated with information and data processing and retrieval (65%) will shift to machines, according to the WEF. People currently working as data entry clerks, accountants and auditors, and factory workers will be most affected even if, as I’ve written, organizations figure out ways to leverage things like AI to enhance worker productivity rather than replace it.

So what happens to these workers? It’s a polite fiction that they’ll simply be re-skilled and adapt to this new AI-automated future. As we’ve seen in past situations where technology automated away jobs, the immediate impact on those workers can be painful. 

Just look at what happened in the telecommunications industry. 

Learning from Ma Bell

As detailed in the aforementioned academic paper “Automation and the Fate of Young Workers: Evidence from Telephone Operation in the Early 20th Century,” written by professors James Feigenbaum and Daniel P. Gross, “Telephone operation, one of the most common jobs for young American women in the early 1900s, provided hundreds of thousands of female workers a pathway into the labor force.” It was a great force for good, but between 1920 and 1940 AT&T (then the dominant telecommunications provider in the US) automated telephone switching in more than half of its network, eliminating hundreds of thousands of jobs. 

So what happened to those women who had been employed as telephone operators?

[T]he automation of telephone operation led to a large, swift, and permanent decline in the number of young, white, American-born women working as operators, of around two-thirds in levels—roughly 2% of total employment for the group (in any job). As it was for many women a transitory job (often, a first job), far more were exposed. For an automation shock, we consider this large, especially for a vulnerable subset of the labor supply. 

Our question is: what happened after these jobs disappeared? Did the elimination of a major entry-level job cut off future generations from entering the workforce? After accounting for concurrent trends taking place in cities of similar size around the country independent of cutovers, we do not find that the shock reduced later cohorts’ employment. We also see no substitution into marriage or childbearing. The negative shock to labor demand was instead counteracted by growth in other occupations, especially secretarial work and restaurant work, which absorbed the women who might have otherwise been telephone operators.

Future generations of would-be telephone operators, in other words, did just fine. The economy took care of creating net new jobs. But for those telephone operators who lost their jobs to automated switching? “While some became operators at private switchboards, others left the workforce, and those who remained employed were more likely to have switched to lower-paying occupations.”

Automation, in short, was good for the overall economy but bad for those whose jobs were automated away. 

SEE: COVID-19 workplace policy (TechRepublic Premium)

Beyond the Luddites

So what do we do? It doesn’t seem practical to destroy the looms as the Luddites once did, attempting to hold back the machines that threatened their jobs. But it’s also not useful to engage in wishful thinking about “upskilling” or “re-skilling.” These are positive endeavors, but it feels like we (by which I mean industry and government, working together) can’t afford to wave away the negative impact technology can have on jobs today. 

Those telephone operators either left the workforce or found lower-paying jobs. Is there something government can do to underwrite some of the costs of helping the modern-day equivalent of the telephone operators to find new jobs? I don’t know. If you have ideas, please comment below or ping me on Twitter (@mjasay). 

Disclosure: I work for AWS, but the views expressed herein are mine.

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Blast from the Past | Technology Org

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Gemini North observations enable breakthrough in centuries-old effort to unravel astronomical mystery.

An international team of astronomers using Gemini North’s GNIRS instrument have discovered that CK Vulpeculae, first seen as a bright new star in 1670, is approximately five times farther away than previously thought. This makes the 1670 explosion of CK Vulpeculae much more energetic than previously estimated and puts it into a mysterious class of objects that are too bright to be members of the well-understood type of explosions known as novae, but too faint to be supernovae.

350 years ago, the French monk Anthelme Voituret saw a bright new star flare into life in the constellation of Vulpecula. Over the following months, the star became almost as bright as Polaris (the North Star) and was monitored by some of the leading astronomers of the day before it faded from view after a year [1]. The new star eventually gained the name CK Vulpeculae and was long considered to be the first documented example of a nova — a fleeting astronomical event arising from an explosion in a close binary star system in which one member is a white dwarf, the remnant of a Sun-like star. However, a string of recent results have thrown the longstanding classification of CK Vulpeculae as a nova into doubt.

Blast from the Past Technology Org

CK Vulpeculae seen with Gemini North. The enigmatic CK Vulpeculae nebula. The team of astronomers measured the speeds and changes in positions of the two small reddish arcs about 1/4 of the way up from the bottom and 1/4 of the way down from the top to help determine that the nebula is expanding five times faster than previously thought. Credit: International Gemini Observatory/NOIRLab/NSF/AURA. Image processing: Travis Rector (University of Alaska Anchorage), Jen Miller (Gemini Observatory/NSF’s NOIRLab), Mahdi Zamani & Davide de Martin

In 2015, a team of astronomers suggested that CK Vulpeculae’s appearance in 1670 was the result of two normal stars undergoing a cataclysmic collision. Just over three years later, the same astronomers further proposed that one of the stars was in fact a bloated red giant star, following their discovery of a radioactive isotope of aluminum in the immediate surroundings of the site of the 1670 explosion. Complicating the picture even further, a separate group of astronomers proposed a different interpretation. In their paper, also published in 2018, they suggested that the sudden brightening in 1670 was the result of the merger between a brown dwarf — a failed star too small to shine via thermonuclear fusion that powers the Sun — and a white dwarf.

Now, adding to the ongoing mystery surrounding CK Vulpeculae, new observations from the international Gemini Observatory, a Program of NSF’s NOIRLab, reveal that this enigmatic astronomical object is much farther away and has ejected gas at much higher speeds than previously reported.

This team, led by Dipankar Banerjee of Physical Research Laboratory Ahmedabad, India, Tom Geballe of Gemini Observatory, and Nye Evans of Keele University in the United Kingdom, initially planned to use the Gemini Near-Infrared Spectrograph (GNIRS) instrument on Gemini North on Hawai‘i’s Maunakea to confirm the 2018 detection of radioactive aluminum at the heart of CK Vulpeculae [2]. After realizing that detecting this in the infrared would be far more difficult than they originally thought, the astronomers improvised and obtained infrared observations across the full extent of CK Vulpeculae, including the two wisps of nebulosity at its outermost edges.

“The key to our discovery was the GNIRS measurements obtained at the outer edges of the nebula,” elaborated Geballe. “The signature of redshifted and blueshifted iron atoms detected there shows that the nebula is expanding much more rapidly than previous observations had suggested.” [3]

As lead author and astronomer Banerjee explains further, “We did not suspect that this is what we would find. It was exciting when we found some gas traveling at the unexpectedly high speed of about 7 million km/hour. This hinted at a different story about CK Vulpeculae than what had been theorized.”

1606313035 394 Blast from the Past Technology Org

Finder chart of CK Vulpeculae. This chart of the position of a new star (marked in red) that appeared in the year 1670 was recorded by the famous astronomer Hevelius and was published by the Royal Society in England in their journal Philosophical Transactions. Credit: Royal Society

By measuring both the speed of the nebula’s expansion and how much the outermost wisps had moved during the last ten years, and accounting for the tilt of the nebula on the night sky, which had been estimated earlier by others, the team determined that CK Vulpeculae lies approximately 10,000 light-years distant from the Sun — about five times as far away as previously thought. That implies that the 1670 explosion was far brighter, releasing roughly 25 times more energy than previously estimated [4]. This much larger estimate of the amount of energy released means that whatever event caused the sudden appearance of CK Vulpeculae in 1670 was far more violent than a simple nova.

“In terms of energy released, our finding places CK Vulpeculae roughly midway between a nova and a supernova,” commented Evans. “It is one of a very few such objects in the Milky Way and the cause — or causes — of the outbursts of this intermediate class of objects remain unknown. I think we all know what CK Vulpeculae isn’t, but no one knows what it is.”

The visual appearance of the CK Vulpeculae nebula and the high velocities observed by the team could help astronomers to recognize relics of similar events — in our Milky Way or in external galaxies — that have occurred in the past.

 

Credit: Images and videos: International Gemini Observatory/NOIRLab/NSF/AURA, K. Pu’uohau-Pummill, A. M. Geller/Northwestern University/CTIO/SOAR. Image processing: Travis Rector (University of Alaska Anchorage), Jen Miller (Gemini Observatory/NSF’s NOIRLab), Mahdi Zamani & Davide de Martin. Music: zero-project – The Lower Dungeons (https://www.zero-project.gr/).

“It is difficult at this stage to offer a definitive or compelling explanation for the origin of the 1670 eruption of CK Vulpeculae,” concluded Banerjee. “Even 350 years after Voituret’s discovery, the nature of the explosion remains a mystery. ”

Notes

[1] 17th-century astronomers who observed the bright new star CK Vulpeculae included distinguished Polish mayor, brewer, and astronomer Johannes Hevelius and the French-Italian astronomer Giovanni Domenico Cassini, who discovered four of Saturn’s moons. After it faded from view in 1671 there were numerous unsuccessful attempts through the intervening centuries to recover it, some by noted astronomers including Halley, Pickering and Humason.

[2] A spectrograph is an instrument that splits light from an astronomical object into its component wavelengths, allowing the composition of the gas emitting the light, its speed, and other traits to be measured.

[3] Just as the pitch of an ambulance siren changes depending on whether the vehicle is moving towards or away from you, astronomical objects change color depending on whether they are moving towards or away from an observer. Objects moving away from Earth become redder (known as redshift) and approaching objects become bluer (known as blueshift).

[4] The brightness of an object is inversely proportional to the square of the distance from an observer. In the case of CK Vulpeculae, if the 1670 explosion occurred five times as far away it must have been 52 = 25 times as bright.

More information

This research is presented in the paper Near-Infrared Spectroscopy of CK Vulpeculae: Revealing a Remarkably Powerful Blast from the Past to appear in the Astrophysical Journal Letters.

The team was composed of D. P. K. Banerjee (Astronomy & Astrophysics Division, Physical Research Laboratory Ahmedabad), T. R. Geballe (Gemini Observatory/NSF’s NOIRLab), A. Evans (Lennard Jones Laboratories, Keele University), M. Shahbandeh (Department of Physics, Florida State University),

C. E. Woodward (Minnesota Institute for Astrophysics, University of Minnesota), R. D. Gehrz (Minnesota Institute for Astrophysics, University of Minnesota), S. P. S. Eyres (Faculty of Computing, Engineering, and Science, University of South Wales), S. Starrfield (School of Earth and Space Exploration, Arizona State University), and A. Zijlstra (Jodrell Bank Centre for Astrophysics, University of Manchester).

Source: Gemini




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