6 papers
Forced Gap Post-Selection for Quantum LDPC Codes and their Operations
Adam Wills, Theodore J. Yoder, Isaac Chuang
We develop a simple and general post-selection strategy for high-rate quantum codes that is transferrable across decoders. After an initial baseline run, the decoder is re-run once…
Machine Learning Decoding of Circuit-Level Noise for Bivariate Bicycle Codes
John Blue, Harshil Avlani, Zhiyang He +2
Fault-tolerant quantum computers will depend crucially on the performance of the classical decoding algorithm which takes in the results of measurements and outputs corrections to…
Thermodynamic Irreversibility of Training Algorithms
Liu Ziyin, Yuanjie Ren, Adam Levine +1
The training algorithms for AI systems all introduce far-from-equilibrium dynamical processes, and understanding the irreversibility of these algorithms is a fundamental step towar…
Quantum Purity Amplification for Arbitrary Eigenstates and Multiple Outputs
Zhaoyi Li, Elias Theil, Aram W. Harrow +1
Quantum purity amplification (QPA) is the task of coherently transforming copies of a mixed state into high-fidelity copies of a chosen eigenstate. We solve QPA in the general…
An Exponential Sample-Complexity Advantage for Coherent Quantum Inference
Zhaoyi Li, Elias Theil, Aram W. Harrow +1
Standard quantum inference converts quantum data into classical outputs. We study an alternative inference setting in which the desired output is quantum, preserving coherence. Suc…
A log-depth in-place quantum Fourier transform that rarely needs ancillas
Gregory D. Kahanamoku-Meyer, John Blue, Thiago Bergamaschi +2
When designing quantum circuits for a given unitary, it can be much cheaper to achieve a good approximation on most inputs than on all inputs. In this work we formalize this idea,…