University at Buffalo physicists have discovered a mathematical solution revealing how a frustrated quantum magnet transitions from ultraslow behavior to dynamics resembling those near a black hole. The team connected spin glasses, states of matter where atomic magnets become effectively frozen, to the fast, entangled states described by the Sachdev-Ye-Kitaev (SYK) model.
“We’ve essentially found the math that describes how matter can go from among the slowest states in quantum dynamics to among the fastest,” says Jamir Marino, PhD, assistant professor of physics and senior lead author of the study published in Physical Review Letters. Understanding this transition could improve control of information storage and spread in future quantum technologies.
SYK Model Links Ultraslow Spin Glasses to Ultrafast Quantum Dynamics
The transition from a frozen state to rapid information scrambling defines a newly understood connection between spin glasses and the behavior predicted by the Sachdev-Ye-Kitaev (SYK) model, originally developed to model black hole physics. Jamir Marino, PhD at Buffalo led a team that mathematically demonstrated how increasing quantum fluctuations can disrupt the ordered arrangement of spins in a spin glass, ultimately leading to the loss of individual particle identities and highly entangled dynamics.
This disruption occurs even as temperature decreases, a counterintuitive finding given that lower temperatures typically reinforce frozen states. Researchers utilized quantum field theory techniques and an unconventional spin representation to probe the behavior of spin glasses at extremely low temperatures, revealing the unexpected pathway to SYK-like dynamics. In a spin glass, the disordered magnetic spins normally respond slowly to external stimuli, preserving information for extended periods and making them potentially useful for data storage and complex problem-solving.
However, the team’s calculations show that amplified quantum fluctuations can overcome this stability, causing the system to transition towards the rapid information scrambling characteristic of the SYK model. “You normally think that lowering the temperature will freeze something even more,” Marino says, highlighting the surprising nature of the result.
The team’s work, published in Physical Review Letters, builds upon the SYK model proposed by Subir Sachdev, PhD, of Harvard University, and Jinwu Ye, establishing a mathematical link between the seemingly disparate phenomena of ultraslow magnetism and the ultrafast entanglement found in systems analogous to black holes.
This connection is not merely theoretical; the researchers demonstrated a specific pathway for this transition, offering insights into controlling information flow in future quantum technologies. “Understanding this transition—and all the states in between—could ultimately help better control the storage and spread of information in quantum technologies,” Marino adds, emphasizing the potential practical applications of their findings. Hossein Hosseinabadi, PhD, formerly of Marino’s lab and now at the Max Planck Institute for the Physics of Complex Systems was first author on the study, contributing to the development of the mathematical framework used to describe the transition.
The team’s findings suggest that the key to unlocking faster quantum dynamics lies in harnessing and manipulating quantum fluctuations within materials, potentially opening new avenues for designing advanced information processing systems. “But here, the quantum effects can essentially melt the spin glass and take you from extremely slow dynamics to extremely fast dynamics,” Marino explains, summarizing the core of their discovery and its implications for understanding the interplay between order and chaos in quantum systems.
You normally think that lowering the temperature will freeze something even more.
Jamir Marino, PhD, assistant professor of physics in the UB College of Arts and Sciences and senior lead
See today’s quantum computing news on Quantum Zeitgeist for the latest breakthroughs in qubits, hardware, algorithms, and industry deals.
