collaborators

7 papers

quant-ph2026

Noise-induced contraction of MPO truncation errors in noisy random circuits and Lindbladian dynamics

Zhi-Yuan Wei, Joel Rajakumar, Jon Nelson +3

We study how matrix-product-operator (MPO) truncation errors evolve when simulating two setups: (1) 1D Haar-random circuits under either depolarizing noise or amplitude-damping noi…

quant-ph2026

Gibbs Sampling gives Quantum Advantage at Constant Temperatures with O(1)-Local Hamiltonians

Joel Rajakumar, James D. Watson

Sampling from Gibbs states -- states corresponding to system in thermal equilibrium -- has recently been shown to be a task for which quantum computers are expected to achieve supe…

quant-ph2026

Measurement-induced entanglement in noisy 2D random circuits

Zhi-Yuan Wei, Jon Nelson, Joel Rajakumar +4

We study measurement-induced entanglement (MIE) generated by column-by-column sampling of noisy 2D random circuits of size and depth . Focusing primarily on Clifford circuit…

quant-ph2026

Polynomial-Time Classical Simulation of Noisy Quantum Circuits with Naturally Fault-Tolerant Gates

Jon Nelson, Joel Rajakumar, Dominik Hangleiter +1

We construct a polynomial-time classical algorithm that samples from the output distribution of noisy geometrically local Clifford circuits with any product-state input and single-…

quant-ph2025

Non-Clifford Gates are Required for Long-Term Memory

Jon Nelson, Joel Rajakumar, Michael J. Gullans

We show that all Clifford circuits under interspersed depolarizing noise lose memory of their input exponentially quickly, even when given access to a constant supply of fresh qubi…

quant-ph2025

Error correction phase transition in noisy random quantum circuits

Jon Nelson, Joel Rajakumar, Michael J. Gullans

In this work, we study the task of encoding logical information via a noisy quantum circuit. It is known that at superlogarithmic depth, the output of any noisy circuit without res…