Latest news with #Zwierlein
Yahoo
09-05-2025
- Science
- Yahoo
For the First Time, Scientists Caught Atoms Freely Interacting in Space—and It Was Stunning
"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Until now, atoms have never been imaged interacting freely in space, but a new technique known as non-resolved microscopy has changed that. MIT physicists were able to successfully capture images of interacting bosons and fermions that were frozen in place and then illuminated. The images proved previous predictions about these types of atoms. This demonstrates that there is real, tangible proof of mathematical predictions in the physical world. What do atoms do when we're not watching? It turns out they do exactly what we thought. Enigmatic because of their quantum nature—meaning that they behave as both particles and waves—atoms had never been visualized freely interacting with each other. Where an atom is and how fast it is moving through space cannot be determined simultaneously. Before, it had been possible to make out the shape and structure of entire clouds of atoms using probes, but the individual atoms within the cloud eluded observation. Now, a team of researchers from MIT have finally managed to capture their interactions for the first time. Led by physicist Martin Zwierlein, the team developed a technique that allowed them to freeze atoms in place and put them in the spotlight with lasers. They were able to successfully image bosons of a sodium isotope and fermions of a lithium isotope before these atoms scattered again. (Bosons—like the infamous Higgs Boson—have spins of integer values, while fermions—like electrons, protons, and neutrons—have odd half-integer spins.) Both isotopes were in the form of quantum gases. Bosons were previously predicted to bunch together in a wave form, exhibiting the wave part of quantum behavior, while fermions were predicted to repel those like them and form pairs with different fermions, which illustrates particle behavior. The probability of finding bosons near each other is high, while there is a low chance of seeing fermions as close together, and the gases needed to be at ultracold temperatures to see anything at all (because atoms get the zoomies when agitated by heat). 'Imaging quantum gases in situ at the resolution of single atoms realizes the ultimate depth of information one may obtain in real space,' Zwierlein and his team said in a study recently published in Physical Review Letters. Their new technique, known as non-resolved microscopy, involves using a laser beam to trap the atoms in one place. There, they are free to interact before they are exposed to a lattice of light that freezes them in place. The atoms are then illuminated with fluorescent light to expose where they are and what they are doing. There was some difficulty in lighting these atoms up, since too much heat would send them flying all over. As a result, this is the first time Zwierlein managed to freeze the motion of strongly interacting atoms in situ, and he was able to capture images of both bosons and fermions. With bosons, the team formed a Bose-Einstein condensate, which is a boson gas cloud cooled to temperatures verging on absolute zero. The MIT team wanted to prove the existing prediction that bosons bunch together because of their high probability of being near each other and their ability to share the same quantum mechanical wave. Atoms in this type of wave show wave-like behavior as they keep changing in time and space, but the properties of those atoms are difficult to observe. The image of bosons shows atoms bunching together with wavelike trails of light behind them, indicating that they are moving in waves. To image a fermion cloud, the team needed two types of fermions—they wanted to capture pairs, and fermions of only one type would end up repelling each other. Sure enough, fermions of the same type avoided each other, while opposite fermions attracted each other. Zwierlein plans to continue using non-resolved microscopy to understand more about the physical world and potentially image stranger, more exotic quantum phenomena. 'This kind of pairing is the basis of a mathematical construction people came up with to explain experiments. But when you see pictures like these, it's showing in a photograph, an object that was discovered in the mathematical world,' Richard Fletcher, a coauthor of the study and physicist from MIT, said in a recent press release. 'So it's a very nice reminder that physics is about physical things. It's real.' You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
07-05-2025
- Science
- Yahoo
In a first, physicists spot elusive 'free-range' atoms — confirming a century-old theory about quantum mechanics
When you buy through links on our articles, Future and its syndication partners may earn a commission. An illustration of atoms floating freely in the air. | Credit: Stanislaw Pytel via Getty Images For the first time, scientists have observed solo atoms floating freely and interacting in space. The discovery helps to confirm some of the most basic principles of quantum mechanics that were first predicted more than a century ago but were never directly verified. Individual atoms are notoriously difficult to observe due to their quantum nature. Researchers cannot, for example, know both an atom's position and its velocity at the same time, due to quantum weirdness. But using certain laser techniques, they have captured images of clouds of atoms . "It's like seeing a cloud in the sky, but not the individual water molecules that make up the cloud," Martin Zwierlein , a physicist at MIT and co-author of the new research, said in a statement . The new method goes one step further, allowing scientists to capture images of "free-range" atoms in free space. First, Zwierlein and his colleagues corralled a cloud of sodium atoms in a loose trap at ultracold temperatures. Then, they shot a lattice of laser light through the cloud to temporarily freeze the atoms in place. A second, fluorescent laser then illuminated the individual atoms' positions. Related: There may be a 'dark mirror' universe within ours where atoms failed to form, new study suggests The observed atoms belong to a group called bosons. These particles share the same quantum mechanical state and, as a result, behave like a wave, bunching together. This concept was first proposed by French physicist Louis de Broglie in 1924 and has subsequently become known as a "de Broglie wave." Top: Two illustrations show how atoms in an atom trap (red) are suddenly frozen in place via an optical lattice. Bottom: Three microscope images show (left to right) bosonic 23Na forming a Bose-Einstein condensate; a single spin state in a weakly interacting 6Li Fermi mixture; and both spin states of a strongly interacting Fermi mixture, directly revealing pair formation. | Credit: Yao et al. Sure enough, the bosons Zwierlein and his team observed displayed de Broglie wave behavior. The researchers also captured images of lithium fermions — a type of particle that repels similar particles rather than bunching together. RELATED STORIES —Physicists create hottest Schrödinger's cat ever in quantum technology breakthrough —Scientists claim to find 'first observational evidence supporting string theory,' which could finally reveal the nature of dark energy —'Einstein's equations need to be refined': Tweaks to general relativity could finally explain what lies at the heart of a black hole The results were published May 5 in the journal Physical Review Letters . Two other groups reported using a similar technique to observe pairs of bosons and fermions in the same issue of the journal. "We are able to see single atoms in these interesting clouds of atoms and what they are doing in relation to each other, which is beautiful," Zwierlein said. In the future, the team plans to use the new technique — called "atom-resolved microscopy" — to investigate other quantum mechanical phenomena. For example, they may use it to try observing the "quantum Hall effect," in which electrons sync up under the influence of a strong magnetic field.
Yahoo
06-05-2025
- Science
- Yahoo
MIT captures first image of free-range atoms, can help visualize quantum phenomena
Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Yahoo is using AI to generate takeaways from this article. This means the info may not always match what's in the article. Reporting mistakes helps us improve the experience. Generate Key Takeaways Scientists from the Massachusetts Institute of Technology (MIT) in the U.S. have made a groundbreaking achievement after they captured the first images of individual atoms freely interacting in space. The images, which show interactions between free-range particles that had only been theorized until now, will reportedly allow the scientists to directly observe quantum phenomena in real space. To capture detailed images of the atomic interactions, the team, led by Martin Zwierlein, PhD, an MIT physicist and lead author of the study, developed a novel technique that allows the atoms to move freely before briefly freezing and illuminating them to capture their positions. The team used the technique to observe clouds of various atom types, capturing several groundbreaking images for the first time. "We are able to see single atoms in these interesting clouds of atoms and what they are doing in relation to each other, which is beautiful," Zwierlein said. Exploring the cloud Atoms are among the tiniest building blocks of the universe, each just one-tenth of a nanometer wide or roughly a million times thinner than a strand of human hair. They additionally follow the strange rules of quantum mechanics making their behavior incredibly difficult to observe and understand. It's impossible to know both an atom's exact position and its speed at the same time - a fundamental principle of quantum physics known as the Heisenberg uncertainty principle. This uncertainty has long challenged scientists trying to observe atomic behavior directly, however, traditional imaging methods, such as absorption imaging, provide only a blurry view, capturing the overall shape of an atom cloud but not the atoms themselves. Now, to overcome the challenge, the team developed a new approach called atom-resolved microscopy, which begins by allowing a cloud of atoms to move and interact freely within a loose laser trap. Bottom: Images show a ²³Na condensate, single-spin ⁶Li, and paired fermions in a Fermi mixture. Credit: Top: Atoms are frozen by an optical lattice and imaged with Raman Images show a ²³Na condensate, single-spin ⁶Li, and paired fermions in a Fermi MIT / Courtesy of the researchers The researchers then switch on a lattice of light to freeze the atoms in place and use a finely tuned laser to illuminate them, causing the atoms to fluoresce - a state when an atom or molecules relaxes through vibrational relaxation to its ground state after being electrically excited - and reveal their exact positions. Capturing this light without disturbing the delicate system was no small feat. "You can imagine if you took a flamethrower to these atoms, they would not like that," Zwierlein explained. "So, we've learned some tricks through the years on how to do this." According to the physicist, what truly makes the technique more powerful than previous methods is that it's the first time they've done it in situ by freezing atoms' motion as they strongly interact and observing them one after another. Quantum snapshots Zwierlein and his colleagues used their new imaging technique to capture quantum interactions between two fundamental types of particles: bosons and fermions. Bosons - among which photons, gluons, the Higgs boson, and the W and Z bosons - which tend to attract, were observed bunching together in a cloud of sodium atoms at low temperatures, forming a Bose-Einstein condensate (BEC) where all particles share the same quantum state. This confirmed a long-standing prediction based on Louis de Broglie's theory that boson bunching is a direct result of their ability to share one quantum wave - a hypothesis known as the de Broglie wave, which helped spark the rise of modern quantum mechanics. "We understand so much more about the world from this wave-like nature," Zwierlein stated. "But it's really tough to observe these quantum, wave-like effects. However, in our new microscope, we can visualize this wave directly." The researchers also imaged a cloud with two types of lithium atoms, each a fermion that typically repels others of its kind but can strongly interact with specific other fermion types. They then captured these opposite fermions pairing up, revealing a key mechanism behind superconductivity. They now plan to apply the technique to explore more complex and less investigated quantum states, including the puzzling behaviors seen in quantum Hall physics. These include scenarios where interacting electrons exhibit unusual correlated behaviors under the influence of a magnetic field. 'That's where theory gets really hairy - where people start drawing pictures instead of being able to write down a full-fledged theory because they can't fully solve it," Zwierlein concludes in a press release. "Now we can verify whether these cartoons of quantum Hall states are actually real. Because they are pretty bizarre states." The study has been published in the journal Physical Review Letters.
