New ‘Seesaw’ Materials Could Supercharge Microchip Encryption at Quantumlike Speeds

Every secure online transaction, encrypted message, and protected password ultimately depends on a stream of numbers that no one, not even the most powerful computer, can predict. The strength of modern digital security rests on this unpredictability, and yet the hardware that produces these random numbers has long been one of the slowest links in the security chain. Now, a team of physicists led in part by Rice University claims to have found a way to break that bottleneck, using an unusual class of materials whose electrical and magnetic properties push against each other like two children on a seesaw. The result, described in a study published in Physical Review Letters, is a theoretical blueprint for security chips that could generate random numbers thousands of times faster than today’s devices, without sacrificing the clarity of the signals that make those numbers usable.

The research was co-led by Jun-Jie Zhang, a postdoctoral research associate in Rice’s Department of Materials Science and Nanoengineering, and Boris Yakobson, the Karl F. Hasselmann Professor in Engineering at Rice. The team also included Shuai Dong, chair of the School of Physics at Southeast University in China. Together, the collaborators explored a class of materials known as autferroics, in which electrical and magnetic order coexist in the same crystal but actively compete rather than simply overlap. That competition, the researchers found, is precisely what makes these materials so promising for one of the most demanding tasks in hardware security: the generation of true random numbers at very high speed.

True random number generators, or TRNGs, are the physical engines of encryption. Unlike the pseudo-random numbers produced by algorithms, which follow deterministic rules and can in principle be reverse-engineered, true random numbers are drawn from genuinely unpredictable physical processes. In many existing security devices, those processes are the tiny thermal fluctuations that jolt miniature magnetic switches between two stable states. Each flip is essentially a coin toss dictated by the chaos of heat at the nanoscale, and stringing together millions of these coin tosses yields the raw entropy that encryption systems require. The problem is speed. In standard devices, the microscopic jumps between magnetic states happen far too slowly to keep up with modern data rates, and the workarounds engineers typically use come at a steep cost.

There are two conventional ways to make a magnetic switch flip faster. One is to shrink the physical components, which lowers the energy barrier between states and allows thermal fluctuations to push the system over more easily. The other is to apply an external magnetic force that actively drives the transition. Both approaches, however, degrade the quality of the signal that carries the random information. When the energy landscape is flattened or forced, the distinction between the two magnetic states blurs, and the electronic readout becomes noisy. A noisy signal means reading errors, and reading errors mean the random bit stream is no longer trustworthy. Security systems that rely on such streams can lag under heavy use or become vulnerable to hacking if the numbers driving encryption are generated too slowly or with weak signals. For years, this trade-off between speed and signal clarity has been a fundamental roadblock for hardware-based randomness.

Autferroic materials bypass the trade-off entirely, according to the team’s theoretical analysis, through a mechanism the researchers describe as seesaw magnetoelectricity. In these materials, the electrical and magnetic states do not coexist passively; they actively push against each other. When the material switches its magnetic orientation, it does not have to force a direct, high-energy leap from one magnetic state to the opposite one. Instead, the switch routes the transition through an intermediate electrical-only step, in which the magnetic order temporarily gives way to a purely electric polarization before the magnetic state re-emerges on the other side. This alternative path lowers the energy barrier by nearly two-thirds, making the flip vastly easier to trigger, while the magnetic state itself remains fully intact on either side of the transition. The magnetic signal, in other words, stays at full strength even as the switching becomes dramatically faster.

Yakobson said the idea emerged from the group’s broader investigations into how physical behavior can be converted into random bits. “Our broader interest in TRNG, or how to extract entropy from physical behavior and convert it into random bits, focused mostly on charge-fluctuating entities in field-effect transistors,” Yakobson explained. “But when exploring the energy landscape of autferroics, especially the lower barrier separating opposite polarizations, Jun-Jie proposed this might lead to faster TRNG. It turned into a very fruitful collaboration with our recent report dovetailing with our previous one.” The observation that a lowered energy barrier could translate directly into faster randomness generation transformed a fundamental materials study into a practical device concept.

The quantitative gains predicted by the team’s computer simulations and dynamic modeling are striking. By lowering the energy barrier through the seesaw mechanism, the switching rate of the magnetic state jumps from under 100 flips per second in a conventional configuration to more than 400,000 flips per second in the autferroic device. At that rate, a single component can generate over a million random bits every second, a throughput that would allow physical security chips to run at top speeds without introducing the electronic reading errors that plague faster conventional devices. Crucially, the team subjected the output of their simulated devices to the official benchmark test suites maintained by the National Institute of Standards and Technology, widely regarded as the gold standard for measuring randomness, and the results passed. “Seesaw magnetoelectricity makes low-energy switching easier without weakening the magnetic state, thereby keeping the readout signal strong,” Zhang said. “It provides clear ‘yes’ or ‘no’ signals, not a ‘maybe.'”

The researchers also identified a way to push the generation process even further. Applying a constant electric field to the material accelerates the switching dynamics, but because the field is uniform and does not favor one magnetic state over the other, the device maintains a perfect 50/50 balance between its two orientations. That balance is essential for pure randomness: any bias toward one outcome would make the bit stream statistically predictable and therefore cryptographically weaker. The electric field acts like a gentle, even-handed push on the seesaw, speeding up the oscillations without tilting the game. The result is a stream of random bits produced at maximum rate with no output bias, which is exactly what encryption algorithms demand.

Beyond faster encryption, the autferroic platform offers a feature that could reshape microchip architecture more broadly. In these materials, both the electric and magnetic degrees of freedom can settle into four distinct, equally stable states rather than the standard binary pair of 0s and 1s. This multistate capability means a single tiny component can carry the information that would otherwise require several conventional transistors. “Four-state autferroic devices can represent more information in a single device,” Zhang explained. “For example, these multistates allow complex numbers, a combination of a real and an imaginary number, to be encoded directly in hardware.” The ability to store complex numbers natively in a physical device is particularly intriguing for advanced computing, where complex arithmetic underpins fields from signal processing to quantum simulation.

The team went a step further and showed, by connecting two of these multistate units to simple circuits, that ordinary microchips could process multistate data and mimic certain aspects of quantum computing by testing multiple outcomes simultaneously. This does not make the device a quantum computer, but it suggests that the same materials strengthening digital encryption could also bring quantumlike parallel processing to standard silicon-based hardware, offering a promising secondary benefit for future chip design. It is important to note that the findings remain theoretical, based on computer models of a two-dimensional nanomaterial known as titanium germanium selenide. Structural imperfections in real manufactured devices may slow the switching speeds somewhat below the simulated values. Even so, the study provides engineers with a clear theoretical foundation for building the next generation of hardware encryption and low-power computing chips. The research at Rice was supported by the U.S. Office of Naval Research, and if experimentalists can realize the seesaw principle in the laboratory, the humble coin toss at the heart of digital security may soon be flipped thousands of times faster than ever before.

Subject of Research: Autferroic materials for high-speed true random number generation in hardware encryption

Article Title: Rice physicists define new material blueprint for next-generation microchip encryption

Article References: Rice physicists define new material blueprint for next-generation microchip encryption. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: autferroics, true random number generators, encryption, magnetoelectricity, Rice University, Physical Review Letters, titanium germanium selenide, 2D materials, multistate computing, NIST randomness tests, hardware security, low-power electronics