Exploring Landauer's Principle with Ultracold Atoms
A groundbreaking study, with contributions from Prof. Spyros Sotiriadis of the University of Crete, has provided new insights into Landauer's principle, a fundamental concept linking information theory and thermodynamics, by observing it dynamically in a quantum many-body system. Published in Nature Physics (DOI: 10.1038/s41567-025-02930-9 <https://doi.org/10.1038/s41567-025-02930-9>), the study reveals how quantum information measures evolve over time and connect to energy dissipation, deepening our understanding of quantum physics and thermodynamics.
Landauer's principle, originally developed in the context of classical computing, asserts that erasing information in a system requires energy dissipation to the environment. In quantum physics, this principle is expressed through a relationship between von Neumann entropy—a quantum information measure— mutual information and relative entropy, which together relate to the energy dissipated as heat. The team's research marks the first experimental observation of the time evolution of these quantities in a quantum many-body system, shedding light on quantum information propagation.
The researchers employed an innovative experimental platform using ultracold atoms manipulated with an atom-chip. This setup enabled a "quantum field simulation," where a quantum many-body system replicates the behaviour of quantum field theory models. By precisely controlling and observing the ultracold atoms, the team tracked the propagation of quantum fields carrying initial correlations throughout the system, verifying theoretical predictions about their dynamics.
To measure the time evolution of the quantum state and extract the relevant information measures, the team used a quantum tomography method. This technique allowed them to reconstruct the quantum state at various points in time, providing a detailed view of how von Neumann entropy, mutual information, and relative entropy evolve, confirming the theoretical framework of Landauer's principle in the quantum regime.
"Our findings demonstrate the power of quantum field simulations using ultracold atoms," said Prof. S. Sotiriadis. The study represents a significant advancement in understanding the interplay between quantum information and energy dissipation. By leveraging cutting-edge experimental techniques, the team has laid a foundation for future investigations into the thermodynamic costs of quantum processes, with potential implications for quantum computing and condensed matter physics.
For more details, read the full paper in Nature Physics (DOI:
10.1038/s41567-025-02930-9 <https://doi.org/10.1038/s41567-025-02930-9>).
