November 2022

Researchers from King Abdullah University of Science and Technology (KAUST) have shown that spintronics-based protective “logic locks” could be incorporated into the integrated circuits of electronic chips to defend chip security. This means that next-gen electronics could feature enhanced security systems built directly into their circuitry to help fend off malicious attacks. 

“The need for hardware-based security features reflects the globalized nature of modern electronics manufacture,” explains Yehia Massoud from KAUST. Electronics companies usually employ large specialized, external foundries to produce their chips, which minimizes costs but introduces potential vulnerabilities to the supply chain. The circuit design could simply be illegally copied by an untrusted foundry for counterfeit chip production or could be maliciously modified by the incorporation of “hardware Trojans” into the circuitry that detrimentally affects its behavior in some way.

Researchers at Beijing Institute of Technology and California Institute of Technology have developed a new theory and numerical calculations to predict spin decoherence in materials with high accuracy. This addresses the issue of spin coherence: quantum states can be easily disrupted, which is a problem when attempting to use them in a device; the electron spins need to preserve their quantum state for as long as possible to avoid loss of information. Spin coherence is so delicate that even the tiny vibrations of the atoms that make up the device can alter the spin state irreversibly.

Marco Bernardi, professor of applied physics, physics and materials science, explains: "Existing theories of spin relaxation and decoherence focus on simple models and qualitative understanding. After years of systematic efforts, my group has developed computational tools to study quantitatively how electrons interact and move in materials. This new paper has taken our work a few steps further: we have adapted a theory of electrical transport to study spin, and discovered that this method can capture two main mechanisms governing spin decoherence in materials—spin scattering off atomic vibrations, and spin precession modified by atomic vibrations. This unified treatment allows us to study the behavior of the electron spin in a wide range of materials and devices essential for future quantum technologies".