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.

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Three-quarters of the world’s population — about 6.1 billion people — now live in countries where freshwater supplies are insecure or critically insecure, according to a U.N. report.

Nature Climate Change, Published online: 22 January 2026; doi:10.1038/s41558-025-02538-0

Changes in ocean fronts could impact biological productivity and carbon exchange. By analysing satellite and reanalysis data, the authors identify areas with active frontal activity and rapid change in properties, as well as highlighting the correspondence with surface productivity and CO2 uptake.

We're taking part in Copyright Week, a series of actions and discussions supporting key principles that should guide copyright policy. Every day this week, various groups are taking on different elements of copyright law and policy, and addressing what's at stake, and what we need to do to make sure that copyright promotes creativity and innovation.

Copyright owners increasingly claim more draconian copyright law and policy will fight back against big tech companies. In reality, copyright gives the most powerful companies even more control over creators and competitors. Today’s copyright policy concentrates power among a handful of corporate gatekeepers—at everyone else’s expense. We need a system that supports grassroots innovation and emerging creators by lowering barriers to entry—ultimately offering all of us a wider variety of choices.

Pro-monopoly regulation through copyright won’t provide any meaningful economic support for vulnerable artists and creators. Because of the imbalance in bargaining power between creators and publishing gatekeepers, trying to help creators by giving them new rights under copyright law is like trying to help a bullied kid by giving them more lunch money for the bully to take.

Entertainment companies’ historical practices bear out this concern. For example, in the late-2000’s to mid-2010’s, music publishers and recording companies struck multimillion-dollar direct licensing deals with music streaming companies and video sharing platforms. Google reportedly paid more than $400 million to a single music label, and Spotify gave the major record labels a combined 18 percent ownership interest in its now- $100 billion company. Yet music labels and publishers frequently fail to share these payments with artists, and artists rarely benefit from these equity arrangements. There’s no reason to think that these same companies would treat their artists more fairly now.

AI Training

In the AI era, copyright may seem like a good way to prevent big tech from profiting from AI at individual creators’ expense—it’s not. In fact, the opposite is true. Developing a large language model requires developers to train the model on millions of works. Requiring developers to license enough AI training data to build a large language model would  limit competition to all but the largest corporations—those that either have their own trove of training data or can afford to strike a deal with one that does. This would result in all the usual harms of limited competition, like higher costs, worse service, and heightened security risks. New, beneficial AI tools that allow people to express themselves or access information.

For giant tech companies that can afford to pay, pricey licensing deals offer a way to lock in their dominant positions in the generative AI market by creating prohibitive barriers to entry.

Legacy gatekeepers have already used copyright to stifle access to information and the creation of new tools for understanding it. Consider, for example, Thomson Reuters v. Ross Intelligence, the first of many copyright lawsuits over the use of works train AI. ROSS Intelligence was a legal research startup that built an AI-based tool to compete with ubiquitous legal research platforms like Lexis and Thomson Reuters’ Westlaw. ROSS trained its tool using “West headnotes” that Thomson Reuters adds to the legal decisions it publishes, paraphrasing the individual legal conclusions (what lawyers call “holdings”) that the headnotes identified. The tool didn’t output any of the headnotes, but Thomson Reuters sued ROSS anyways. A federal appeals court is still considering the key copyright issues in the case—which EFF weighed in on last year. EFF hopes that the appeals court will the in this overbroad interpretation of copyright law. But in the meantime, the case has already forced the startup out of business, eliminating a would-be competitor that might have helped increase access to the law.

Requiring developers to license AI training materials benefits tech monopolists as well. For giant tech companies that can afford to pay, pricey licensing deals offer a way to lock in their dominant positions in the generative AI market by creating prohibitive barriers to entry. The cost of licensing enough works to train an LLM would be prohibitively expensive for most would-be competitors.

The DMCA’s “Anti-Circumvention” Provision

The Digital Millennium Copyright Act’s “anti-circumvention” provision is another case in point. Congress ostensibly passed the DMCA to discourage would-be infringers from defeating Digital Rights Management (DRM) and other access controls and copy restrictions on creative works.

Section 1201 has been used to block competition and innovation in everything from printer cartridges to garage door openers

In practice, it’s done little to deter infringement—after all, large-scale infringement already invites massive legal penalties. Instead, Section 1201 has been used to block competition and innovation in everything from printer cartridges to garage door openers, videogame console accessories, and computer maintenance services. It’s been used to threaten hobbyists who wanted to make their devices and games work better. And the problem only gets worse as software shows up in more and more places, from phones to cars to refrigerators to farm equipment. If that software is locked up behind DRM, interoperating with it so you can offer add-on services may require circumvention. As a result, manufacturers get complete control over their products, long after they are purchased, and can even shut down secondary markets (as Lexmark did for printer ink, and Microsoft tried to do for Xbox memory cards.)

Giving rights holders a veto on new competition and innovation hurts consumers. Instead, we need balanced copyright policy that rewards consumers without impeding competition.

Robert Liebeck, a professor of the practice in the MIT Department of Aeronautics and Astronautics and one of the world’s leading experts on aircraft design, aerodynamics, and hydrodynamics, died on Jan. 12 at age 87.

“Bob was a mentor and dear friend to so many faculty, alumni, and researchers at AeroAstro over the course of 25 years,” says Julie Shah, department head and the H.N. Slater Professor of Aeronautics and Astronautics at MIT. “He’ll be deeply missed by all who were fortunate enough to know him.”

Liebeck’s long and distinguished career in aerospace engineering included a number of foundational contributions to aerodynamics and aircraft design, beginning with his graduate research into high-lift airfoils. His novel designs came to be known as “Liebeck airfoils” and are used primarily for high-altitude reconnaissance airplanes; Liebeck airfoils have also been adapted for use in Formula One racing cars, racing sailboats, and even a flying replica of a giant pterosaur.

He was perhaps best known for his groundbreaking work on blended wing body (BWB) aircraft. He oversaw the BWB project at Boeing during his celebrated five-decade tenure at the company, working closely with NASA on the X-48 experimental aircraft. After retiring as senior technical fellow at Boeing in 2020, Liebeck remained active in BWB research. He served as technical advisor at BWB startup JetZero, which is aiming to build a more fuel-efficient aircraft for both military and commercial use and has set a target date of 2027 for its demonstration flight. 

Liebeck was appointed a professor of the practice at MIT in 2000, and taught classes on aircraft design and aerodynamics. 

“Bob contributed to the department both in aircraft capstones and also in advising students and mentoring faculty, including myself,” says John Hansman, the T. Wilson Professor of Aeronautics and Astronautics. “In addition to aviation, Bob was very significant in car racing and developed the downforce wing and flap system which has become standard on F1, IndyCar, and NASCAR cars.”

He was a major contributor to the Silent Aircraft Project, a collaboration between MIT and Cambridge University led by Dame Ann Dowling. Liebeck also worked closely with Professor Woody Hoburg ’08 and his research group, advising on students’ research into efficient methods for designing aerospace vehicles. Before Hoburg was accepted into the NASA astronaut corps in 2017, the group produced an open-source Python package, GPkit, for geometric programming, which was used to design a five-day endurance unmanned aerial vehicle for the U.S. Air Force.

“Bob was universally respected in aviation and he was a good friend to the department,” remembers Professor Ed Greitzer.

Liebeck was an AIAA honorary fellow and Boeing senior technical fellow, as well as a member of the National Academy of Engineering, Royal Aeronautical Society, and Academy of Model Aeronautics. He was a recipient of the Guggenheim Medal and ASME Spirit of St. Louis Medal, among many other awards, and was inducted into the International Air and Space Hall of Fame.

An avid runner and motorcyclist, Liebeck is remembered by friends and colleagues for his adventurous nature and generosity of spirit. Throughout a career punctuated by honors and achievements, Liebeck found his greatest satisfaction in teaching. In addition to his role at MIT, he was an adjunct faculty member at University of California at Irving and served as faculty member for that university’s Design/Build/Fly and Human-Powered Airplane teams.

“It is the one job where I feel I have done some good — even after a bad lecture,” he told AeroAstro Magazine in 2007. “I have decided that I am finally beginning to understand aeronautical engineering, and I want to share that understanding with our youth.”

We're taking part in Copyright Week, a series of actions and discussions supporting key principles that should guide copyright policy. Every day this week, various groups are taking on different elements of copyright law and policy, and addressing what's at stake, and what we need to do to make sure that copyright promotes creativity and innovation.

There’s a crisis of creativity in mainstream American culture. We have fewer and fewer studios and record labels and fewer and fewer platforms online that serve independent artists and creators.  

At its core, copyright is a monopoly right on creative output and expression. It’s intended to allow people who make things to make a living through those things, to incentivize creativity. To square the circle that is “exclusive control over expression” and “free speech,” we have fair use.

However, we aren’t just seeing artists having a time-limited ability to make money off of their creations. We are also seeing large corporations turn into megacorporations and consolidating huge stores of copyrights under one umbrella. When the monopoly right granted by copyright is compounded by the speed and scale of media company mergers, we end up with a crisis in creativity. 

People have been complaining about the lack of originality in Hollywood for a long time. What is interesting is that the response from the major studios has rarely, especially recently, to invest in original programming. Instead, they have increased their copyright holdings through mergers and acquisitions. In today’s consolidated media world, copyright is doing the opposite of its intended purpose: instead of encouraging creativity, it’s discouraging it. The drive to snap up media franchises (or “intellectual properties”) that can generate sequels, reboots, spinoffs, and series for years to come has crowded out truly original and fresh creativity in many sectors. And since copyright terms last so long, there isn’t even a ticking clock to force these corporations to seek out new original creations. 

In theory, the internet should provide a counterweight to this problem by lowering barriers to entry for independent creators. But as online platforms for creativity likewise shrink in number and grow in scale, they have closed ranks with the major studios.  

It’s a betrayal of the promise of the internet: that it should be a level playing field where you get to decide what you want to do, watch, listen to, read. And our government should be ashamed for letting it happen.  

No matter how many times we say it, the idea comes back again and again. Hopefully, this letter will hold back the tide for at least a while longer.

Executive summary: Scientists have understood for many years that internet voting is insecure and that there is no known or foreseeable technology that can make it secure. Still, vendors of internet voting keep claiming that, somehow, their new system is different, or the insecurity doesn’t matter. Bradley Tusk and his Mobile Voting Foundation keep touting internet voting to journalists and election administrators; this whole effort is misleading and dangerous...

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