CAREER: Explore Quantum Many-Body Dynamics Beyond Thermalization

About This Grant

NONTECHNICAL SUMMARY This award supports theoretical research and associated education on the dynamics of quantum systems. Recent experimental breakthroughs in a variety of quantum systems have made it possible to isolate and control many interacting quantum particles over extended periods of time. Due to interactions among the particles, these systems often appear to settle into equilibrium and remain static, a process known as thermalization. However, unlike in classical systems, the underlying quantum state continues to evolve in time, even when the system looks static on the surface. The quantum state contains complete information about the system. The time evolution of the quantum state can give rise to universal quantum phenomena with no classical counterpart. Building on recent developments in quantum many-body physics and quantum information science, this research explores the rich, hidden dynamics of quantum states that persist even after local equilibrium is reached, aiming to uncover universal behavior - properties that are independent of the details of a quantum many-body system, and to harness the complex quantum states for novel quantum technologies, such as new quantum error correction codes. This project incorporates educational activities aimed to train undergraduate and graduate students and disseminate quantum science to broader audiences. The research team will make a quantum booth showcasing interactive demos and games at public events and on social media to illustrate the core concepts and ideas of quantum mechanics. Additionally, the PI will work with local high school teachers through workshops focused on developing strategies to introduce quantum concepts into their curricula. TECHNICAL SUMMARY Integrating tools from quantum many-body physics and quantum information science, this research combines analytical and numerical approaches to study quantum many-body dynamics along three main thrusts: (i) revealing how unitary dynamics scramble local information into non-local entanglement and developing a general decoding protocol using the Petz recovery map; (ii) investigating how symmetries constrain and enable control over scrambling through the transport of conserved quantities; and (iii) characterizing the largely unexplored long-time behavior of many-body unitary dynamics using higher-order Green’s functions on multi-folded Keldysh contours to uncover new dynamical regimes. The overarching goal is to understand universal many-body dynamics beyond thermalization across different time scales and to harness the entanglement and complexity of the time-dependent quantum states for novel quantum technologies. For instance, insights into how unitary dynamics scramble information could lead to new quantum many-body teleportation protocol and new quantum error correction codes that store and protect quantum information beyond the stabilizer formalism; understanding the role of symmetries may enable manipulation of stored quantum information via conserved quantities; and exploring the post-scrambling regime after local information is fully scrambled may reveal new time scales of quantum many-body dynamics and new ways to exploit the complex structure of quantum states. This project incorporates educational activities aimed to train undergraduate and graduate students and disseminate quantum science to broader audiences. The research team will make a quantum booth showcasing interactive demos and games at public events and on social media to illustrate the core concepts and ideas of quantum mechanics. Additionally, the PI will work with local high school teachers through workshops focused on developing strategies to introduce quantum concepts into their curricula. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.