7 papers
Quantum Codeword Sensing
John Blue, Zachary E. Chin, Vlad S. Oros +1
Consider the task of identifying an unknown classical codeword delivered to a register of quantum sensor qubits through a sequence of weak phase interactions that each encode one b…
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…
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 develop a general theory…
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. Such settings include qua…
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,…
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…