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MIT engineers develop a magnetic transistor for more energy-efficient electronics

MIT Latest News - Wed, 09/23/3035 - 10:32am

Transistors, the building blocks of modern electronics, are typically made of silicon. Because it’s a semiconductor, this material can control the flow of electricity in a circuit. But silicon has fundamental physical limits that restrict how compact and energy-efficient a transistor can be.

MIT researchers have now replaced silicon with a magnetic semiconductor, creating a magnetic transistor that could enable smaller, faster, and more energy-efficient circuits. The material’s magnetism strongly influences its electronic behavior, leading to more efficient control of the flow of electricity. 

The team used a novel magnetic material and an optimization process that reduces the material’s defects, which boosts the transistor’s performance.

The material’s unique magnetic properties also allow for transistors with built-in memory, which would simplify circuit design and unlock new applications for high-performance electronics.

“People have known about magnets for thousands of years, but there are very limited ways to incorporate magnetism into electronics. We have shown a new way to efficiently utilize magnetism that opens up a lot of possibilities for future applications and research,” says Chung-Tao Chou, an MIT graduate student in the departments of Electrical Engineering and Computer Science (EECS) and Physics, and co-lead author of a paper on this advance.

Chou is joined on the paper by co-lead author Eugene Park, a graduate student in the Department of Materials Science and Engineering (DMSE); Julian Klein, a DMSE research scientist; Josep Ingla-Aynes, a postdoc in the MIT Plasma Science and Fusion Center; Jagadeesh S. Moodera, a senior research scientist in the Department of Physics; and senior authors Frances Ross, TDK Professor in DMSE; and Luqiao Liu, an associate professor in EECS, and a member of the Research Laboratory of Electronics; as well as others at the University of Chemistry and Technology in Prague. The paper appears today in Physical Review Letters.

Overcoming the limits

In an electronic device, silicon semiconductor transistors act like tiny light switches that turn a circuit on and off, or amplify weak signals in a communication system. They do this using a small input voltage.

But a fundamental physical limit of silicon semiconductors prevents a transistor from operating below a certain voltage, which hinders its energy efficiency.

To make more efficient electronics, researchers have spent decades working toward magnetic transistors that utilize electron spin to control the flow of electricity. Electron spin is a fundamental property that enables electrons to behave like tiny magnets.

So far, scientists have mostly been limited to using certain magnetic materials. These lack the favorable electronic properties of semiconductors, constraining device performance.

“In this work, we combine magnetism and semiconductor physics to realize useful spintronic devices,” Liu says.

The researchers replace the silicon in the surface layer of a transistor with chromium sulfur bromide, a two-dimensional material that acts as a magnetic semiconductor.

Due to the material’s structure, researchers can switch between two magnetic states very cleanly. This makes it ideal for use in a transistor that smoothly switches between “on” and “off.”

“One of the biggest challenges we faced was finding the right material. We tried many other materials that didn’t work,” Chou says.

They discovered that changing these magnetic states modifies the material’s electronic properties, enabling low-energy operation. And unlike many other 2D materials, chromium sulfur bromide remains stable in air.

To make a transistor, the researchers pattern electrodes onto a silicon substrate, then carefully align and transfer the 2D material on top. They use tape to pick up a tiny piece of material, only a few tens of nanometers thick, and place it onto the substrate.

“A lot of researchers will use solvents or glue to do the transfer, but transistors require a very clean surface. We eliminate all those risks by simplifying this step,” Chou says.

Leveraging magnetism

This lack of contamination enables their device to outperform existing magnetic transistors. Most others can only create a weak magnetic effect, changing the flow of current by a few percent or less. Their new transistor can switch or amplify the electric current by a factor of 10.

They use an external magnetic field to change the magnetic state of the material, switching the transistor using significantly less energy than would usually be required.

The material also allows them to control the magnetic states with electric current. This is important because engineers cannot apply magnetic fields to individual transistors in an electronic device. They need to control each one electrically.

The material’s magnetic properties could also enable transistors with built-in memory, simplifying the design of logic or memory circuits.

A typical memory device has a magnetic cell to store information and a transistor to read it out. Their method can combine both into one magnetic transistor.

“Now, not only are transistors turning on and off, they are also remembering information. And because we can switch the transistor with greater magnitude, the signal is much stronger so we can read out the information faster, and in a much more reliable way,” Liu says.

Building on this demonstration, the researchers plan to further study the use of electrical current to control the device. They are also working to make their method scalable so they can fabricate arrays of transistors.

This research was supported, in part, by the Semiconductor Research Corporation, the U.S. Defense Advanced Research Projects Agency (DARPA), the U.S. National Science Foundation (NSF), the U.S. Department of Energy, the U.S. Army Research Office, and the Czech Ministry of Education, Youth, and Sports. The work was partially carried out at the MIT.nano facilities.

Jazz in the key of life

MIT Latest News - 4 hours 29 min ago

It is not hard to find glowing reviews of saxophonist Miguel Zenón, a creative jazz artist whose compositions incorporate musical elements from his native Puerto Rico.

For instance, The Jazz Times called “Jibaro,” Zenón’s breakthrough 2005 album, “profound yet joyful.” The New York Times called the same music “strong and light,” adding that we have “rarely seen a jazz composer step forward with a project so impressively organized, intellectually powerful and well played from the start.”

In 2009, when Zenón won a prestigious MacArthur Fellowship, the MacArthur Foundation called Zenón’s work “elegant and innovative,” with “a high degree of daring and sophistication.” In 2012, The New York Times reviewed another Zenón work, “Puerto Rico Nació en Mi: Tales From the Diaspora,” by calling the music “deeply hybridized and original, complex but clear.”

As you may have noticed, these notices all contain multiple descriptive terms. That’s because Zenón’s work is many things at once: jazz, combined with other musical genres; technically rigorous, and supple; novel, yet steeped in tradition. Indeed, Zenón has always seen jazz as being multifaceted.

“What I discovered, when I first encountered jazz, was this idea that you were using improvisation to portray your personality directly to your listeners,” Zenón explains. “And it was connected to a very interesting and intricate improvisational language. That provided something I hadn’t encountered in music before, this idea that you could have something personal and heartfelt walking hand in hand with something that was intellectual and brainy. That balance spoke to me.”

It is still speaking. In 2024, Zenón won the Grammy Award for Best Latin Jazz Album for “El Arte Del Bolero Vol. 2,” a collaboration with Venezuelan pianist Luis Perdomo, a musical partner in the Miguel Zenón Quartet.

Zenón has taught at MIT for three years now. He became a tenured faculty member last year, in MIT’s Music and Theater Arts program, where he helps students find the same satisfaction in music that he does.

“When I first got into music, I was looking for fulfillment,” Zenón says. “It wasn’t about success. I was just looking for music to fulfill something within me. And I still search for that now. And sometimes it still feels like it did 25 or 30 years ago, when I first encountered that feeling. It’s nice to have that in your pocket, to say, this is what I’m looking for, that initial feeling.”

Paradise in the Back Bay

Zenón grew up in San Juan, Puerto Rico. Around age 11, he started attending a performing arts school and playing the saxophone. In his last year of school, Zenón was admitted into college to study engineering. However, a few years before, he had encountered something new: jazz. Zenón’s training had been in classical music. But jazz felt different.

“Discovering jazz music ignited a passion for music in me that had not existed up to that point,” says Zenón, who decided to pursue music in college. “I kind of jumped ship, and it was a blind jump. I didn’t know what to expect, I didn’t know what was on the other side, I didn’t have any artists or any musicians in my family. I just followed a hunch, followed my heart.”

After teachers recommended he study at the renowned Berklee College of Music in Boston, Zenón worked to find a scholarship and funding.

“This was way before the internet. I was looking at catalogs,” Zenón recalls. “I had never been to Boston in my life, I didn’t even know what Berklee looked like. But at Berklee it was the first time I was able to connect with a jazz teacher in a formal way, to learn about history, theory, harmony, and I soaked in it. Also, I was surrounded by young people like myself, who were as enamored and passionate about music as I was. It really felt like paradise.”

After earning his BA from Berklee in 1998, Zenón then moved to New York City. He earned an MA from the Manhattan School of Music in 2001 and began playing more extensively with new bandmates.

“I just wanted to be able to play with people who were better than me, and learn from the experience,” Zenón says. He started generating new ideas, writing music, and performing publicly. With Antonio Sánchez, Hans Glawischnig, and Perdomo, he founded the Miguel Zenón Quartet.

“That led to going into the studio and making an album,” Zenón recounts. “And that led to more experience, and more albums.”

Did it ever. Zenón has now been the leader for about 20 albums, mostly featuring the quartet. (After several years, Henry Cole replaced Sánchez as the group’s drummer.) Zenón has played on many recordings by other artists, and helped found the SFJAZZ Collective.

Not many prolific musicians will name any one recording as their best, and Zenón is the same way, but he is willing to cite a few that were milestones for him.

“Jibaro” draws on the music of Puerto Rico’s jibaro singers, troubadors using 10-line stanzas with eight-syllable lines, something Zenón adopted for jazz-quartet use. “Esta Plena,” a 2009 record, fuses jazz and the structures of “plena,” a traditional percussion-based Puerto Rican song form. “Alma Adentro,” a 2011 album, covers classic songs from Puerto Rico.

“It would be impossible for me to pick one favorite, but what I would say is, there are a couple of albums in the earlier part of my career that explored a balance between things coming from a jazz world and coming from traditional Puerto Rican traditional music and folklore, when I was able to feel like that balance was right, it felt like me,” Zenón says. “This is what I have to give. This is my persona.”

In 2008, Zenón was also honored with a Guggenheim Fellowship, which helped him conduct music research, another facet of his career. Zenón has often extensively interviewed traditional Puerto Rican musicians about the intricacies of their works before writing material in those forms.

And Zenón has made a point of giving back, founding the Caravana Cultural, a project that brings free jazz concerts to rural Puerto Rico.

Work, joy, and love

Zenón is now settled in at MIT, which boasts a vibrant music program. More than 1,500 MIT students take a music class each year, and over 500 students participate in one of 30 campus ensembles. Last year, MIT opened its new Edward and Joyce Linde Music Building, a purpose-built performance, rehearsal, and teaching space.

“There are definitely students at MIT who could be at some of the best music schools in the world,” Zenón says. “That’s not in question.”

Moreover, among MIT students, Zenón says, “There is a communal approach to music. Everything they do, they do for each other. They look out for each other, they work together. And that has been one of the most rewarding things to see.”

He continues: “Of course the students are brilliant and the faculty are too. In terms of what I like to teach, it’s been a good fit for me personally, and I couldn’t be happier about the opportunity. There’s more and more interest in jazz, more and more interest in creating things together, and there’s a unique mindset being built in front of our eyes.”

He is also pleased to work in the Linde Music Building: “It’s amazing to have the building, not only in terms of the facilities, but it’s also a symbol of the place music has within the Institute. We’re not just talking about music, we’re creating it. It’s a great commitment from the school and says a lot about our leadership.”

Meanwhile, along with teaching, Zenón’s own recording career continues at full speed. With Luis Perdomo, he is working on “El Arte Del Bolero Vol. 3,” the follow-up to his Grammy-winning album. And Zenón has plans for still another album, to be recorded in Puerto Rico with a large ensemble, based on music he is writing about Puerto Rico’s history and present.

“Things are always linked,” Zenón explains. “Once you finish one project, the next one starts. It feels natural for me to do it that way.”

In conversation, Zenón is engaging, genial, and reflective. So what advice does he have for younger musicians? Not everyone who plays an instrument will become Miguel Zenón. But what about people who want to pursue music, not knowing how far it will take them?

“If you find something you enjoy, just enjoy it for the sake of it,” Zenón says. “Find what brings joy, and make sure you don’t lose that. Having said that, with music, like any art form, or anything else in life, in order to make progress, it takes work and commitment. There’s no hiding that. So if music is something you’re serious about, set goals you can achieve over time, so you always have something to work for. In my experience, that’s key. But I always pair that with the idea of joy and love for music — keeping that love close to your heart.”

Professor Emeritus Jack Dennis, pioneering developer of dataflow models of computation, dies at 94

MIT Latest News - Fri, 04/10/2026 - 5:40pm

Jack Dennis, an influential MIT professor emeritus of computer science and engineering, died on March 14 at age 94. The original leader of the Computation Structures Group within the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL), he pioneered the development of dataflow models of computation, and, subsequently, many novel principles of computer architecture inspired by dataflow models.

The second child of an engineer and a textile designer, Dennis showed early interest in both engineering and music, rewriting Gilbert and Sullivan lyrics with his parents and playing piano with the Norwalk Symphony Orchestra in Connecticut as a teen, while building a canoe at home with his father. As an undergraduate at MIT, he developed his wide array of interests further, joining the VI-A Cooperative Program in Electrical Engineering; working at the Air Force Cambridge Research Laboratories on projects in speech processing and novel radar systems; participating in the model railroad club; and joining the MIT Symphony Orchestra, where he met his first wife, Jane Hodgson ’55, SM ’56, PhD ’61. (The two later separated when she went to study medicine in Florida.) 

Dennis earned his BS (1953), MS (1954), and ScD (1958) from MIT before joining the then-Department of Electrical Engineering as a faculty member. He was promoted to full professor status in 1969. His doctoral thesis, entitled, “Mathematical Programming and electrical networks,” explored analogies between electric circuit theory and quadratic programming problems. Ideas he developed in that paper further crystallized in his 1964 paper, “Distributed solution of network programming problems,” which created an important early class of digital distributed optimization solvers.

In a 2003 piece that Dennis wrote for his undergraduate class’s 50th reunion, he remembered his earliest encounters with computers at the Institute: “I prepared programs written in assembly language on punched paper tape using Frieden 'Flexowriters,' and stood aside watching the myriad lights blink and flash while operator Mike Solamita fed the tapes [...] That was 1954. Fifty years later, much has changed: A room full of vacuum tubes has become a tiny chip with millions of transistors. A phenomenon once limited to research laboratories has become an industry producing commodity products that anyone can own and use beneficially.”

Dennis’ influence in steering that change was profound. As a collaborator with the teams behind both Project MAC and Multics, the earliest attempts to allow multiple users to work with a single computer seemingly simultaneously (i.e., a time-shared operating system), Dennis helped to specify the unique segment addressing and paging mechanisms that became a fundamental part of the General Electric Model 645 computer. His insights stemmed from a tendency to pay equal attention to both hard- and software when others considered themselves specialists in one or the other. 

“I formed the Computation Structures Group [within CSAIL] and focused on architectural concepts that could narrow the acknowledged gap between programming concepts and the organization of computer hardware,” Dennis explained in his 2003 recollection. “I found myself dismayed that people would consider themselves to be either hardware or software experts, but paid little heed to how joint advances in programming and architecture could lead to a synergistic outcome that might revolutionize computing practice.”

Dennis’ emphasis on synergy did not go unnoticed. Gerald Sussman, the Panasonic Professor of Electrical Engineering, points out “the relationship of [Dennis’] dataflow architecture to single-assignment programs, and thus to pure functional programs. This coupled the virtue of referential transparency in programming to the effective use of hardware parallelism. Dennis also pioneered the use of self-timed circuits in digital systems. The ideas from that work generalize to much of the work on highly distributed systems.” 

The Computation Structures Group attracted multiple scholars interested in developing asynchronous computing and dataflow architecture, many of whom became lifelong friends and collaborators. These included Peter Denning, with whom Dennis and Joseph Qualitz co-authored the textbook “Machines, Languages, and Computation” (1978); the late Arvind, who became faculty head of computer science for the Department of Electrical Engineering and Computer Science (EECS), and the late Guang R. Gao, who became distinguished professor of electrical and computer engineering at the University of Delaware. 

In recognition of his contributions to the Multics project, Dennis was elected fellow of the Institute of Electrical and Electronics Engineers (IEEE). Many additional honors would follow: He received the Association for Computing Machinery (ACM)/IEEE Eckert-Mauchly Award in 1984; was inducted as a fellow of the ACM (1994); was named to the National Academy of Engineering (2009); was elected to the (ACM) Special Interest Group on Operating Systems (SIGOPS) Hall of Fame (2012); and was awarded the IEEE John von Neumann Medal (2013). 

A successful researcher, Dennis was perhaps equally influential in the development of EECS’ curriculum, developing six subjects in areas of computer theory and systems: Theoretical Models for Computation; Computation Structures; Structure of Computer Systems; Semantic Theory for Computer Systems; Semantics of Parallel Computation; and Computer System Architecture (taught in collaboration with Arvind.) Several of the courses that Dennis developed continue to be taught, in updated form, to this day.

Following his retirement from teaching in 1987, he consulted on projects relating to parallel computer hardware and software for such varied groups as NASA Research Institute for Advanced Computer Science; Boeing Aerospace; McGill University; the Architecture Group of Carlstedt Elektronik in Gothenburg, Sweden; and Acorn Networks, Inc. His fruitful relationship with former student Guang Gao continued in the form of a lecture tour through China, as well as co-authorship of a book, “Dataflow Architecture,” currently in progress at MIT Press. 

A voracious lifelong learner, Dennis was fond of repeating a friend’s observation that “a scholar is just a book’s way of making another book.” In a full and active retirement, he still made room for music, trying his hand at composing; performing at Tanglewood as a tenor in Chorus Pro Musica; playing piano at the marriage of Guang Gao’s son Nick; and joining the chorus at the First Church in Belmont, Massachusetts, where his celebration of life (with concurrent livestreaming) will be held on Monday, June 8, at 2 p.m. 

Dennis is survived by his wife Therese Smith ’75; children David Hodgson Dennis of North Miami, Florida; Randall Dennis of Connecticut; and Galen Dennis, a resident of Australia. 

Friday Squid Blogging: Squid Overfishing in the South Pacific

Schneier on Security - Fri, 04/10/2026 - 5:03pm

Regulation is hard:

The South Pacific Regional Fisheries Management Organization (SPRFMO) oversees fishing across roughly 59 million square kilometers (22 million square miles) of the South Pacific high seas, trying to impose order on a region double the size of Africa, where distant-water fleets pursue species ranging from jack mackerel to jumbo flying squid. The latter dominated this year’s talks.

Fishing for jumbo flying squid (Dosidicus gigas) has expanded rapidly over the past two decades. The number of squid-jigging vessels operating in SPRFMO waters rose from 14 in 2000 to more than 500 last year, almost all of them flying the Chinese flag. Meanwhile, reported catches have fallen markedly, from more than 1 million metric tons in 2014 to about 600,000 metric tons in 2024. Scientists worry that fishing pressure is outpacing knowledge of the stock. ...

We Need You: Our Privacy Cannot Afford a Clean Extension of Section 702

EFF: Updates - Fri, 04/10/2026 - 9:50am

We go through this every couple of years: Section 702 of the Foreign Intelligence Surveillance Act (FISA), which of Americans’ communications with foreign persons overseas is up for renewal. As always, Congress can reauthorize it with or without changes, or just let it expire. We know, we know, it’s a pain to have to do this every few years–but it gives us a chance to lift the hood of this behemoth tool of government surveillance and tinker with how it works. That’s why it’s so important right now to urge your Member of Congress not to pass any bill that reauthorizes Section 702 without substantial reforms.   

Take action

TELL congress: 702 Needs Reform

Section 702 is rife with problems, loopholes, and compliance issues that need fixing. The National Security Agency (NSA) collects full conversations being conducted by surveillance targets overseas and stores them, allowing the Federal Bureau of Investigation (FBI) to operate in a “finders keepers” mode of surveillance—they reason that it's already collected, so why can’t they look at those conversations? There, the FBI can query and even read the U.S. side of that communication without a warrant. The problem is, people who have been spied on by this program won’t even know and have very few ways of finding out. EFF and other civil liberties advocates have been trying for years to know when data collected through Section 702 is used as evidence against them.  

There’s simply no excuse for any Member of Congress to support a "clean" reauthorization of Section 702. Anyone who votes to do so does not take your privacy seriously. Full stop.  

The intelligence community and its defenders in Congress, as always, seem more interested in defending their rights to read your private communications than in protecting your right to privacy. It’s not really a compromise between safety and privacy if it's always your privacy that gets sacrificed. Now, we’re drawing a line in the sand: Congress cannot pass a clean extension.  

Use this EFF tool to write to your Member of Congress and tell them not to pass a clean reauthorization of Section 702.  

Take action

TELL congress: 702 Needs Reform

Sen. Sanders Talks to Claude About AI and Privacy

Schneier on Security - Fri, 04/10/2026 - 6:41am

Claude is actually pretty good on the issues.

Iran war propels Asia’s EV market

ClimateWire News - Fri, 04/10/2026 - 6:31am
By attacking Iran, President Donald Trump has indirectly boosted an industry he has done his best to weaken in the U.S.

3 coal turbines ordered to stay open by DOE have not run

ClimateWire News - Fri, 04/10/2026 - 6:30am
Energy Secretary Chris Wright said the retiring plants were needed to potentially save lives. None of them have generated power.

Trump said to approve first disaster request in 7 weeks

ClimateWire News - Fri, 04/10/2026 - 6:28am
Approval of aid for Hawaii came one day after the new Homeland Security secretary vowed to address a backlog of requests.

9th Circuit rejects youth climate lawsuit against EPA

ClimateWire News - Fri, 04/10/2026 - 6:26am
The West Coast federal appeals court found the group of young people couldn't tie their alleged climate injuries to the agency's policies.

Texas prison heat case in judge’s hands

ClimateWire News - Fri, 04/10/2026 - 6:25am
Prisoners and nonprofit advocates await a decision from a federal judge after asking him to declare state prison conditions unconstitutional.

Turning Point turbocharged this Arizona utility race

ClimateWire News - Fri, 04/10/2026 - 6:23am
Clean energy advocates are now the majority on the board of an Arizona utility giant, after the far-right group boosted voter turnout to record-smashing levels.

California lawmakers call for more flexibility in carbon market rewrite

ClimateWire News - Fri, 04/10/2026 - 6:23am
Bipartisan lawmakers warn a tighter emissions cap could drive up costs and industrial flight.

Oregon court ruling could jeopardize $1B in wildfire victim damages

ClimateWire News - Fri, 04/10/2026 - 6:22am
The Oregon Court of Appeals sent a class-action case against PacifiCorp back to a lower trial court over concerns about a jury instruction given during a 2023 trial.

EU signals soft approach to methane emissions rule enforcement

ClimateWire News - Fri, 04/10/2026 - 6:21am
Oil and gas firms complain the rules, designed to limit global warming, could jeopardize EU energy supplies.

Argentina approves Milei’s bill that eases protections for glaciers

ClimateWire News - Fri, 04/10/2026 - 6:20am
Opposition lawmakers have labeled the legislation unconstitutional, contending that it rolls back essential environmental protections.

15 years of change

Nature Climate Change - Fri, 04/10/2026 - 12:00am

Nature Climate Change, Published online: 10 April 2026; doi:10.1038/s41558-026-02610-3

Since Nature Climate Change was launched, not only has the journal itself changed but so have the subjects of the studies we publish on the Earth system and how societies interact with it. In this Infographic, we highlight a few examples of how the world differed when we started in 2011 compared with today.

Research that captures a changing world

Nature Climate Change - Fri, 04/10/2026 - 12:00am

Nature Climate Change, Published online: 10 April 2026; doi:10.1038/s41558-026-02623-y

This month marks 15 years since the first publication of Nature Climate Change. Here, we reflect on how both the world and research have changed, and discuss the impacts of memorable climate change science published in our pages.

Atlantic exceptionalism in the twentieth century

Nature Climate Change - Fri, 04/10/2026 - 12:00am

Nature Climate Change, Published online: 10 April 2026; doi:10.1038/s41558-026-02608-x

The North Atlantic is exceptional in cooling during the twentieth century while the world warmed. Here we look back on an influential 2015 study that linked this cooling to a weakening of the Atlantic Meridional Overturning Circulation and consider the wider implications that this may have for climate, ecosystems and society.

Early-career researchers reflect on influential papers

Nature Climate Change - Fri, 04/10/2026 - 12:00am

Nature Climate Change, Published online: 10 April 2026; doi:10.1038/s41558-026-02605-0

As Nature Climate Change celebrates its 15 year anniversary, we look back at some of the journal’s published works. In this Viewpoint, seven early-career researchers discuss how these papers influenced their research and careers.

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