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A new thermal transistor can control heat as precisely as an electrical transistor can control electricity.
From smartphones to supercomputers, electronics have a heat problem. Modern computer chips suffer from microscopic “hotspots” with power density levels that exceed those of rocket nozzles and even approach that of the sun’s surface. Because of this, more than half the total electricity burned at U.S. data centers isn’t used for computing but for cooling. Many promising new technologies—such as 3-D-stacked chips and renewable energy systems—are blocked from reaching their full potential by errant heat that diminishes a device’s performance, reliability, and longevity.
“Heat is very challenging to manage,” says Yongjie Hu, a physicist and mechanical engineer at the University of California, Los Angeles. “Controlling heat flow has long been a dream for physicists and engineers, yet it’s remained elusive.”
But Hu and his colleagues may have found a solution. As reported last November in Science, his team has developed a new type of transistor that can precisely control heat flow by taking advantage of the basic chemistry of atomic bonding at the single-molecule level. These “thermal transistors” will likely be a central component of future circuits and will work in tandem with electrical transistors. The novel device is already affordable, scalable, and compatible with current industrial manufacturing practices, Hu says, and it could soon be incorporated into the production of lithium-ion batteries, combustion engines, semiconductor systems (such as computer chips), and more.
Japan and the European Union have officially inaugurated testing at the world’s largest experimental nuclear fusion plant. Located roughly 85 miles north of Tokyo, the six-story JT-60SA “tokamak” facility heats plasma to 200 million degrees Celsius (around 360 million Fahrenheit) within its circular, magnetically insulated reactor. Although JT-60SA first powered up during a test run back in October, the partner governments’ December 1 announcement marks the official start of operations at the world’s biggest fusion center, reaffirming a “long-standing cooperation in the field of fusion energy.”
The tokamak—an acronym of the Russian-language designation of “toroidal chamber with magnetic coils”—has led researchers’ push towards achieving the “Holy Grail” of sustainable green energy production for decades. Often described as a large hollow donut, a tokamak is filled with gaseous hydrogen fuel that is then spun at immense high speeds using powerful magnetic coil encasements. When all goes as planned, intense force ionizes atoms to form helium plasma, much like how the sun produces its energy.
Speaking at the inauguration event, EU energy commissioner Kadri Simson referred to the JT-60SA as “the most advanced tokamak in the world,” representing “a milestone for fusion history.”
“Fusion has the potential to become a key component for energy mix in the second half of this century,” she continued.
High-dimensional quantum transport enabled by nonlinear detection. In our concept, information is encoded on a coherent source and overlapped with a single photon from an entangled pair in a nonlinear crystal for up-conversion by sum frequency generation, the latter acting as a nonlinear spatial mode detector. The bright source is necessary to achieve the efficiency required for nonlinear detection. Information and photons flow in opposite directions: one of [the] Bob’s entangled photons is sent to Alice and has no information, while a measurement on the other in coincidence with the upconverted photon establishes the transport of information across the quantum link. Alice need not know this information for the process to work, while the nonlinearity allows the state to be arbitrary and unknown dimension and basis. Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-43949-x
Nature Communicationspublished research by an international team from Wits and ICFO- The Institute of Photonic Sciences, which demonstrates the teleportation-like transport of “patterns” of light—this is the first approach that can transport images across a network without physically sending the image and a crucial step towards realizing a quantum network for high-dimensional entangled states.
Quantum communication over long distances is integral to information security and has been demonstrated with two-dimensional states (qubits) over very long distances between satellites. This may seem enough if we compare it with its classical counterpart, i.e., sending bits that can be encoded in 1s (signal) and 0s (no signal), one at a time.
However, quantum optics allow us to increase the alphabet and to securely describe more complex systems in a single shot, such as a unique fingerprint or a face.
“Traditionally, two communicating parties physically send the information from one to the other, even in the quantum realm,” says Prof. Andrew Forbes, the lead PI from Wits University.
“Now, it is possible to teleport information so that it never physically travels across the connection—a ‘Star Trek’ technology made real.” Unfortunately, teleportation has so far only been demonstrated with three-dimensional states (imagine a three-pixel image); therefore, additional entangled photons are needed to reach higher dimensions.
Cate Cox and Brittany Watts: Their last names rhyme, but their circumstances couldn’t be more diametrically different from one another.
Cate Cox is a married suburban mother with two children. She previously lived in a suburb of Dallas, Texas, but due to her condition, she had to flee her state. A complication with her pregnancy put her life at risk and the possibility that she might not be able to conceive again if her pregnancy weren’t ended expeditiously through a procedure now outlawed in Texas.
Brittany Watts, an African American woman, had a stillborn, unfortunately, in the toilet. The fetus was found in the drain, and she was charged with abuse.
Mrs. Cox eventually left Texas for the procedure, having the financial means to leave and get the healthcare that she desired.
Ms. Watts was a frightened young woman who had left the hospital twice before her miscarriage. Yet she’s charged with felony abuse of a corpse in Ohio.
Abstract
The Effects of the Dobbs Decision on Fertility*
The U.S. Supreme Court decision in Dobbs v. Jackson Women’s Health Organization sparked the most profound transformation of the landscape of abortion access in 50 years. We provide the first estimates of the effects of this decision on fertility using a preregistered synthetic difference-in-differences design applied to newly released provisional natality data for the first half of 2023. The results indicate that states with abortion bans experienced an average increase in births of 2.3 percent relative to states where abortion was not restricted.
The Dobbs Decision was a strategic salvo shot at the year 2045:
New census population projections confirm the importance of racial minorities as the primary demographic engine of the nation’s future growth, countering an aging, slow-growing, and soon-to-be-declining white population. The new statistics project that the nation will become “minority white” in 2045. During that year, whites will comprise 49.7 percent of the population in contrast to 24.6 percent for Hispanics, 13.1 percent for blacks, 7.9 percent for Asians, and 3.8 percent for multiracial populations (see Figure 1).
The shift is the result of two trends. First, between 2018 and 2060, gains will continue in the combined racial minority populations, growing by 74 percent. Second, during this time frame, the aging white population will see a modest immediate gain through 2024 and then experience a long-term decline through 2060, a consequence of more deaths than births (see Figure 2)
24.6 (Hispanics) + 13.1 (African Americans) + 7.9 (Asians) + 3.8 (Multiracial) + 0.9 (Other) = 50.3%, which is apparently an existential crisis on the right because “white” supremacy is anxiously numerical.
In a democratic society, the numerical majority wins, rules, and decides. The theoretical rights of a minority may or may not be respected, especially if they are a planned minority. Numerical population power is the power that comes to those groups that acquire power through their sheer size. The black population peaked in the 1750s when slaves and free blacks accounted for approximately 33 percent of the total population. The high numerical strength of blacks caused fear and concern among whites. They feared the loss of their own numerical power. Word of black Haitians’ successful slave revolt in the 1790s had spread across America and reportedly ignited several slave revolts in Southern states.
The First U.S. Congress enacted the first naturalization law that declared America to be a nation for “whites only.” The Naturalization Act and other income incentives attracted a mass influx of legal and illegal European ethnicities, followed by Asian and Hispanic immigrants a century later. The immigration quota for blacks remained zero until their total percentage of the population declined to nine percent. By making blacks a planned numerical minority, white society assured its dominance in a democratic society where the majority always wins. Source: Sample chapter
Hence, a national ban is actually what they want. Fifteen weeks will be sold as a “reasonable” compromise, and then it will be paired down to the goose egg that is the actual target. Hence, the hostility towards mixed-race couples and multiracial children from their union: they’re not on the “white” team. Hence, the hostility towards the LGBTQ community and whether or not they conceive by surrogate or artificial insemination, their union does not produce enough “white” babies to maintain a numerical majority for the “white” team. Mrs. Cox and upper-middle-class suburban women like her will always have the means and the money to flee any complications and save future childbearing years. Ms. Watt will have one of two options: either flush her undesired fetus while in a state of shock down a toilet or die from complications that she cannot afford to mitigate.
The American Eugenics Movement, unfortunately, had a boost from prominent scientists who wished to rid the world of the “feebleminded” and the unfit. They did this through forced sterilization and control over who could get married (to procreate in the first place). If you’ve ever used the terms “well-bred” or “good breeding,” those originate from eugenics, now accepted as a pseudoscience, once promoted by one of the founders of the transistor and Nobel laureate in Physics, William Schockley. Coupled with southern Jim Crow, eugenics-on-steroids in the hands of the Nazis led to the Holocaust.
Nazi authorities created the Lebensborn program to increase Germany’s population. Pregnant German women deemed “racially valuable” were encouraged to give birth to their children at Lebensborn homes. During World War II, the program became complicit in the kidnapping of foreign children with physical features considered “Aryan” by the Nazis.
The First U.S. Congress enacted the first naturalization law that declared America to be a nation for “whites only.” The Naturalization Act and other income incentives attracted a mass influx of legal and illegal European ethnicities, followed by Asian and Hispanic immigrants a century later. The immigration quota for blacks remained zero until their total percentage of the population declined to nine percent. By making blacks a planned numerical minority, white society assured its dominance in a democratic society where the majority always wins. Source: Sample chapter
If one is desperate to maintain a majority or “goose your numbers,” you might be capable of anything to achieve those ends.
Very soon in the founding of a new nation, however, White Christians began to establish their well-being by using the resources, bodies, and lives of others. Through their own “witchcraft,” European Christians employed a mysterious and threatening potency that was the practice of using the other for their own gain. In [James W.] Perkinson’s description, through the projects of modern Christian empire “a witchery” of heretofore unimaginable potency ravaged African and aboriginal cultures…For Perkinson, the witchcraft of White supremacy was conjured through racial discourse as an ideological and practical frame that he identifies as the ‘quintessential witchery of modernity.’… In Perkinson’s chilling words, “Whiteness, under the veneer of its ‘heavenly’ pallor, is a great grinding witch tooth, sucking blood and tearing flesh without apology.”
Researchers are working to overcome challenges related to nanoscale optoelectronic interconnects, which use light to transmit signals around an integrated circuit. IMAGE: PROVIDED BY NCNST
The promise of nanotechnology, the engineering of machines and systems at the nanoscale, is anything but tiny. Over the past decade alone, there has been an explosion in research on how to design and build components that solve problems across almost every sector, and nanotechnology innovations have led to huge advancements in our quest to address humanity’s grand challenges, from healthcare to water to food security.
Like any area of scholarship, there are still so many unknowns. And yet, there are more talented scientists and engineers endeavoring to better comprehend and harness the power of nanotechnology than ever before. The future is bright for nanotechnology and its applications.
In celebration of its 20th anniversary, the National Center for Nanoscience and Technology, China (NCNST), a subsidiary of the prestigious Chinese Academy of Sciences, partnered with Science Custom Publishing to survey nanoscience experts from the journal and across the globe about the most knotty and fascinating questions that still need to be answered if we are to advance nanotechnology in society.
The 3D model of Menga was drawn with AutoCAD, showing the biofacies (microfacies) present in the stones. The fourth pillar, currently missing, has been added, while capstones C-2, C-3, C-4, and C-5 have been removed in order to show the interior of the monument (Lozano Rodríguez et al.25). (a) Pillar P-3 with examples of biofacies (a1–a3 observed in hand specimen). (b) Orthostat O-15 with examples of biofacies (b1–b4 observed petrographically) and in hand specimen (b5). (c) Orthostat O-8 with examples observed petrographically (crossed polars) (c1,c2). (d) Orthostat O-5 with examples observed through the petrographic microscope (d1,d2). The star-shaped symbol indicates the place where a section was made for the petrographic study. Qtz: Quartz (designations after Kretz,49).
Topics: Applied Physics, Archaeology, Dark Humor, History
Abstract
The technical and intellectual capabilities of past societies are reflected in the monuments they were able to build. Tracking the provenance of the stones utilized to build prehistoric megalithic monuments through geological studies is of utmost interest for interpreting ancient architecture as well as contributing to their protection. According to the scarce information available, most stones used in European prehistoric megaliths originate from locations near the construction sites, which would have made transport easier. The Menga dolmen (Antequera, Malaga, Spain), listed in UNESCO World Heritage since July 2016, was designed and built with stones weighing up to nearly 150 tons, thus becoming the most colossal stone monument built in its time in Europe (c. 3800–3600 BC). Our study (based on high-resolution geological mapping as well as petrographic and stratigraphic analyses) reveals key geological and archaeological evidence to establish the precise provenance of the massive stones used in the construction of this monument. These stones are mostly calcarenites, a poorly cemented detrital sedimentary rock comparable to those known as ‘soft stones’ in modern civil engineering. They were quarried from a rocky outcrop located at a distance of approximately 1 km. In this study, it can be inferred the use of soft stone in Menga reveals the human application of new wood and stone technologies, enabling the construction of a monument of unprecedented magnitude and complexity.
José Antonio Lozano Rodríguez, Leonardo García Sanjuán, Antonio M. Álvarez-Valero, Francisco Jiménez-Espejo, Jesús María Arrieta, Eugenio Fraile-Nuez, Raquel Montero Artús, Giuseppe Cultrone, Fernando Alonso Muñoz-Carballeda & Francisco Martínez-Sevilla
In this image, optical pulses (solitons) can be seen circling through conjoined optical tracks. (Image: Yuan, Bowers, Vahala, et al.) An animated gif is at the original link below.
(Nanowerk News) When we last checked in with Caltech’s Kerry Vahala three years ago, his lab had recently reported the development of a new optical device called a turnkey frequency microcomb that has applications in digital communications, precision timekeeping, spectroscopy, and even astronomy.
This device, fabricated on a silicon wafer, takes input laser light of one frequency and converts it into an evenly spaced set of many distinct frequencies that form a train of pulses whose length can be as short as 100 femtoseconds (quadrillionths of a second). (The comb in the name comes from the frequencies being spaced like the teeth of a hair comb.)
Now Vahala, Caltech’s Ted and Ginger Jenkins, Professor of Information Science and Technology and Applied Physics and executive officer for applied physics and materials science, along with members of his research group and the group of John Bowers at UC Santa Barbara, have made a breakthrough in the way the short pulses form in an important new material called ultra-low-loss silicon nitride (ULL nitride), a compound formed of silicon and nitrogen. The silicon nitride is prepared to be extremely pure and deposited in a thin film.
In principle, short-pulse microcomb devices made from this material would require very low power to operate. Unfortunately, short light pulses (called solitons) cannot be properly generated in this material because of a property called dispersion, which causes light or other electromagnetic waves to travel at different speeds, depending on their frequency. ULL has what is known as normal dispersion, and this prevents waveguides made of ULL nitride from supporting the short pulses necessary for microcomb operation.
In a paper appearing in Nature Photonics (“Soliton pulse pairs at multiple colors in normal dispersion microresonators”), the researchers discuss their development of the new micro comb, which overcomes the inherent optical limitations of ULL nitride by generating pulses in pairs. This is a significant development because ULL nitride is created with the same technology used for manufacturing computer chips. This kind of manufacturing technique means that these microcombs could one day be integrated into a wide variety of handheld devices similar in form to smartphones.
The most distinctive feature of an ordinary microcomb is a small optical loop that looks a bit like a tiny racetrack. During operation, the solitons automatically form and circulate around it.
“However, when this loop is made of ULL nitride, the dispersion destabilizes the soliton pulses,” says co-author Zhiquan Yuan (MS ’21), a graduate student in applied physics.
Imagine the loop as a racetrack with cars. If some cars travel faster and some travel slower, then they will spread out as they circle the track instead of staying as a tight pack. Similarly, the normal dispersion of ULL means light pulses spread out in the microcomb waveguides, and the microcomb ceases to work.
The solution devised by the team was to create multiple racetracks, pairing them up so they look a bit like a figure eight. In the middle of that ‘8,’ the two tracks run parallel to each other with only a tiny gap between them.
Often referred to as the “dream batteries,” all-solid-state batteries are the next generation of batteries that many battery manufacturers are competing to bring to market. Unlike lithium-ion batteries, which use a liquid electrolyte, all components, including the electrolyte, anode, and cathode, are solid, reducing the risk of explosion, and are in high demand in markets ranging from automobiles to energy storage systems (ESS).
However, devices that maintain the high pressure (10s of MPa) required for stable operation of all-solid-state batteries have problems that reduce the battery performance, such as energy density and capacity, and must be solved for commercialization.
Dr. Hun-Gi Jung and his team at the Energy Storage Research Center at the Korea Institute of Science and Technology (KIST) have identified degradation factors that cause rapid capacity degradation and shortened lifespan when operating all-solid-state batteries at pressures similar to those of lithium-ion batteries. The research is published in the journal Advanced Energy Materials.
Unlike previous studies, the researchers confirmed for the first time that degradation can occur inside the cathode as well as outside, showing that all-solid-state batteries can be operated reliably even in low-pressure environments.
In all-solid-state batteries, the cathode and anode have a volume change during repeated charging and discharging, resulting in interfacial degradation, such as side reaction and contact loss between active materials and solid electrolytes, which increase the interfacial resistance and worsen cell performance.
To solve this problem, external devices are used to maintain high pressure, but this has the disadvantage of reducing energy density as the weight and volume of the battery increase. Research is being conducted on the inside of the all-solid-state cell to maintain the performance of the cell, even in low-pressure environments.
I can hear an irritated counterthrust already. The president has not driven the United States into a recession during his almost seven years in office. Unemployment stands at a respectable 4.6 percent. Well, fine. But the other side of the ledger groans with distress: a tax code that has become hideously biased in favor of the rich; a national debt that will probably have grown 70 percent by the time this president leaves Washington; a swelling cascade of mortgage defaults; a record near-$850 billion trade deficit; oil prices that are higher than they have ever been; and a dollar so weak that for an American to buy a cup of coffee in London or Paris—or even the Yukon—becomes a venture in high finance.
And it gets worse. After almost seven years of this president, the United States is less prepared than ever to face the future. We have not been educating enough engineers and scientists, people with the skills we will need to compete with China and India. We have not been investing in the kinds of basic research that made us the technological powerhouse of the late 20th century. And although the president now understands—or so he says—that we must begin to wean ourselves from oil and coal, we have become more deeply dependent on both on his watch.
Up to now, the conventional wisdom has been that Herbert Hoover, whose policies aggravated the Great Depression, is the odds-on claimant for the mantle of “worst president” regarding stewardship of the American economy. Once Franklin Roosevelt assumed office and reversed Hoover’s policies, the country began to recover. The economic effects of Bush’s presidency are more insidious than those of Hoover, harder to reverse, and likely to be longer-lasting. There is no threat of America’s being displaced from its position as the world’s richest economy. But our grandchildren will still be living with and struggling with the economic consequences of Mr. Bush.
I am enjoying the New York Times bestseller by former Congresswoman Liz Cheney, Oath and Honor: A Memoir and a Warning. The book was sold out, so I bought the CDs to play on my car’s player as I casually drive to and from work. There are 11 CDs, and from the few I’ve listened to, she has an hour’s worth of material for each. The book is 384 pages.
I enjoy her erudite writing and observations of our current moment and crisis. Though we probably don’t agree on many things, I admire her integrity, love of her parents (particularly her dad), her family, and demonstrated fidelity to the US Constitution.
However, her dad was a part of the administration that Nobel laureate Dr. Stiglitz discusses in his Vanity Fair article. It was her dad who, instead of searching for a VP candidate, nominated himself. It was her dad who championed the disastrous war in Iraq, a country that did not attack us on September 11, 2001. He didn’t just “sex up” the intelligence about weapons of mass destruction in Iraq; he lied. That license led to thousands of Iraqis killed and the fertile ground from which sprang Al-Qaeda in Iraq, followed by ISIS. That license led to pathological licentiousness to lie more than 30,000 times in a four-year presidential term. “Deficits don’t matter” leads to truth not mattering—Post hoc ergo proctor hoc.
It was her dad who said:
“You know, Paul, Reagan proved deficits don’t matter,” he said, according to excerpts. Cheney continued: “We won the midterms [congressional elections]. This is our due.” A month later, in December 2002, Cheney told the Treasury secretary he was fired.
I remember reading this on my Kindle: The Price of Loyalty: George W. Bush, the White House, and the Education of Paul O’Neill, Ron Suskind. For Liz’s dad, deficits didn’t matter. That drove the drunken stupor of tax cuts that led to the cliff we almost fell off in 2008. There was a real crisis when the Obama-Biden administration took office after the financial crash spawned by the “deficits don’t matter” philosophy.
Wall Street was, of course, bailed out over Main Street. COVID bailouts benefitted the rich. That’s why Wall Street is more than willing to do it again. Until we see some CEOs and Hedge Fund Managers frog-marched in shackles, what onus stops them?
The Dow Jones hit a record 37,000+ Thursday. Yet, we’re into how we “feel” about the economy. I don’t think it’s “feelings.”
Inflation soared across the globe last year, peaking near 11% in the eurozone and above 9% in the US.
The source of that high inflation has become a well-trodden line. Analysts have typically laid the blame on supply-chain bottlenecks created by excess demand during the COVID-19 pandemic and exacerbated by Russia’s invasion of Ukraine.
The war also increased energy prices, leading to further rises in inflation as suppliers factored in higher transport and running costs.
While this contributed to rising prices, the report finds that company profits increased at a much faster rate than costs did, in a process often dubbed “greedflation.”
Profits for companies in some of the world’s largest economies rose by 30% between 2019 and 2022, significantly outpacing inflation, according to the group’s research of 1,350 firms across the US, the UK, Europe, Brazil, and South Africa.
The biggest perpetrators were energy companies like Shell, Exxon Mobil, and Chevron, which were able to enjoy massive profits last year as demand moved away from Russian oil and gas.
A June study by the International Monetary Fund (IMF) found that 45% of eurozone inflation in 2022 could be attributed to domestic profits. Companies in a position to benefit most from higher commodity prices and supply-demand mismatches raised their profits by the most, the study found.
CEOs of the world’s biggest companies consistently sounded the alarm on inflation as a significant barrier to growth. Many blamed rising input costs on their own price hikes. However, lots of those CEOs appear to have instead used the panic of rising costs to pump up their balance sheet.
In essence, gaslighting is the psychological manipulation of a person, usually over an extended period of time, that causes the victim to question the validity of their own thoughts, perception of reality, or memories and typically leads to confusion, loss of confidence and self-esteem, uncertainty of one’s emotional or mental stability, and a dependency on the perpetrator—the act or practice of grossly misleading someone, especially for one’s own advantage. Election season can create emotions spanning from immense anxiety all the way to extreme apathy. The public arguing, divisiveness, and competition for votes, including political gaslighting, can be overwhelming and exhausting.—Vernita Perkins and Leonard A. Jason,Merriam-Webster.
Political gaslighting has one objective: to undermine the truth, or more accurately, to undermine objective truth.
“Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.” Winston Smith, in “1984” by George Orwell. Under torture, O’Brien makes Winston say he sees five fingers when O’Brien is holding up four. The Party was the arbiter of truth, and “truth” was whatever the Party or O’Brien said it was.
“There are FOUR lights!” Jean Luc Picard shouted defiantly under torture by Gul Madred in Star Trek: The Next Generation: “Chain of Command, part II.”
There are strategies to combat gaslighting. Despair can be debilitating and a self-fulfilling prophecy if the worst possible outcome that you can think of happens.
The best strategy I know to combat despair is to work on a campaign that you’re passionate about. In 2012, it didn’t look like Barack Obama and Joe Biden would get re-elected against Mitt Romney and Paul Ryan (former Speaker of the House – remember him?). My wife and I volunteered to call from the campaign office of Sean Patrick Maloney, who we had never heard of. He won and became our Congressman as long as we lived in New York. He sadly lost his seat when congressional districts were redrawn, so he was competing for the same votes as another Democrat.
The best weapon against gaslighting is truth.
Liz Cheney is telling the truth and bringing receipts—truth matters.
She quotes her dad on the second CD, who admonished her to “save the republic, daughter,” missing the irony his “deficits don’t matter” rhetoric spawned what we’re all living through.
Take heart. Tell the truth. Truth matters in the face of lies. Grind it out next year and vote.
Chromatic imaging of white light with a single lens (left) and achromatic imaging of white light with a hybrid lens (right). Credit: The Grainger College of Engineering at the University of Illinois Urbana-Champaign
Topics: 3D Printing, Additive Manufacturing, Applied Physics, Materials Science, Optics
Using 3D printing and porous silicon, researchers at the University of Illinois Urbana-Champaign have developed compact, visible wavelength achromats that are essential for miniaturized and lightweight optics. These high-performance hybrid micro-optics achieve high focusing efficiencies while minimizing volume and thickness. Further, these microlenses can be constructed into arrays to form larger area images for achromatic light-field images and displays.
This study was led by materials science and engineering professors Paul Braun and David Cahill, electrical and computer engineering professor Lynford Goddard, and former graduate student Corey Richards. The results of this research were published in Nature Communications.
“We developed a way to create structures exhibiting the functionalities of classical compound optics but in highly miniaturized thin film via non-traditional fabrication approaches,” says Braun.
In many imaging applications, multiple wavelengths of light are present, e.g., white light. If a single lens is used to focus this light, different wavelengths focus at different points, resulting in a color-blurred image. To solve this problem, multiple lenses are stacked together to form an achromatic lens. “In white light imaging, if you use a single lens, you have considerable dispersion, and so each constituent color is focused at a different position. With an achromatic lens, however, all the colors focus at the same point,” says Braun.
The challenge, however, is that the required stack of lens elements required to make an achromatic lens is relatively thick, which can make a classical achromatic lens unsuitable for newer, scaled-down technological platforms, such as ultracompact visible wavelength cameras, portable microscopes, and even wearable devices.
Physics and Nano 