9 papers
Detecting vortex motion through spatially correlated nonequilibrium noise
Yifan F. Zhang, Rhine Samajdar, Sarang Gopalakrishnan
Resistive transport near a superconducting phase can arise from the motion of normal-state quasiparticles or that of vortices. The conductivity alone does not distinguish between t…
Stability of mixed-state phases under weak decoherence
Yifan F. Zhang, Sarang Gopalakrishnan
We prove that the Gibbs states of classical, and commuting-Pauli, Hamiltonians are stable under weak local decoherence: i.e., we show that the effect of the decoherence can be loca…
Classically Sampling Noisy Quantum Circuits in Quasi-Polynomial Time under Approximate Markovianity
Yifan F. Zhang, Su-un Lee, Liang Jiang +1
While quantum computing can accomplish tasks that are classically intractable, the presence of noise may destroy this advantage in the absence of fault tolerance. In this work, we…
Conditional Mutual Information and Information-Theoretic Phases of Decohered Gibbs States
Yifan Zhang, Sarang Gopalakrishnan
Classical and quantum Markov networks -- including Gibbs states of commuting local Hamiltonians -- are characterized by the vanishing of conditional mutual information (CMI) betwee…
Classical Simulability of Quantum Circuits with Shallow Magic Depth
Yifan Zhang, Yuxuan Zhang
Quantum magic is a necessary resource for quantum computers to be not efficiently simulable by classical computers. Previous results have linked the amount of quantum magic, charac…
Characterizing MPS and PEPS Preparable via Measurement and Feedback
Yifan Zhang, Sarang Gopalakrishnan, Georgios Styliaris
Preparing long-range entangled states poses significant challenges for near-term quantum devices. It is known that measurement and feedback (MF) can aid this task by allowing the p…