11 papers
A Unified Framework for Locally Stable Phases
Zhi Li, Raz Firanko, Timothy H. Hsieh
We propose a unifying framework for characterizing pure and mixed state phases of matter across equilibrium, non equilibrium, and metastable regimes. We introduce the concept of lo…
Unlearnable phases of matter
Tarun Advaith Kumar, Yijian Zou, Amir-Reza Negari +2
We identify fundamental limitations in machine learning by demonstrating that non-trivial mixed-state phases of matter are computationally hard to learn. Focusing on unsupervised l…
Mixed-state Quantum Phases: Renormalization and Quantum Error Correction
Shengqi Sang, Yijian Zou, Timothy H. Hsieh
Open system quantum dynamics can generate a variety of long-range entangled mixed states, yet it has been unclear in what sense they constitute phases of matter. To establish that…
Critical non-equilibrium phases from noisy topological memories
Amir-Reza Negari, Subhayan Sahu, Jan Behrends +2
We demonstrate the existence of an extended non-equilibrium critical phase, characterized by sub-exponential decay of conditional mutual information (CMI), in the surface code subj…
Autoregressive Typical Thermal States
Tarun Advaith Kumar, Leon Balents, Timothy H. Hsieh +1
A variety of generative neural networks recently adopted from machine learning have provided promising strategies for studying quantum matter. In particular, the success of autoreg…
Mixed-state phases from local reversibility
Shengqi Sang, Leonardo A. Lessa, Roger S. K. Mong +3
We propose a refined definition of mixed-state phase equivalence based on locally reversible channel circuits. We show that such circuits preserve topological degeneracy and the lo…