Encoding electronic spectra in quantum circuits with linear T complexity

R Babbush, C Gidney, DW Berry, N Wiebe, J McClean… - Physical Review X, 2018 - APS
We construct quantum circuits that exactly encode the spectra of correlated electron models
up to errors from rotation synthesis. By invoking these circuits as oracles within the recently …

Equivalence of restricted Boltzmann machines and tensor network states

J Chen, S Cheng, H Xie, L Wang, T Xiang - Physical Review B, 2018 - APS
The restricted Boltzmann machine (RBM) is one of the fundamental building blocks of deep
learning. RBM finds wide applications in dimensional reduction, feature extraction, and …

Halving the cost of quantum addition

C Gidney - Quantum, 2018 - quantum-journal.org
We improve the number of T gates needed to perform an n-bit adder from $8 n+ O (1) $ to $4
n+ O (1) $. We do so via a" temporary logical-AND" construction which uses four T gates to …

Ultrahigh error threshold for surface codes with biased noise

DK Tuckett, SD Bartlett, ST Flammia - Physical review letters, 2018 - APS
We show that a simple modification of the surface code can exhibit an enormous gain in the
error correction threshold for a noise model in which Pauli Z errors occur more frequently …

Optimizing the nonlinearity and dissipation of a snail parametric amplifier for dynamic range

NE Frattini, VV Sivak, A Lingenfelter, S Shankar… - Physical Review …, 2018 - APS
We present a quantum-limited Josephson-junction-based three-wave-mixing parametric
amplifier, the superconducting nonlinear asymmetric inductive element (SNAIL) parametric …

[HTML][HTML] Flag fault-tolerant error correction with arbitrary distance codes

C Chamberland, ME Beverland - Quantum, 2018 - quantum-journal.org
In this paper we introduce a general fault-tolerant quantum error correction protocol using
flag circuits for measuring stabilizers of arbitrary distance codes. In addition to extending flag …

[HTML][HTML] Machine-learning-assisted correction of correlated qubit errors in a topological code

P Baireuther, TE O'Brien, B Tarasinski… - Quantum, 2018 - quantum-journal.org
A fault-tolerant quantum computation requires an efficient means to detect and correct errors
that accumulate in encoded quantum information. In the context of machine learning, neural …

Correcting coherent errors with surface codes

S Bravyi, M Englbrecht, R König, N Peard - npj Quantum Information, 2018 - nature.com
Surface codes are building blocks of quantum computing platforms based on 2D arrays of
qubits responsible for detecting and correcting errors. The error suppression achieved by …

Deep neural decoders for near term fault-tolerant experiments

C Chamberland, P Ronagh - Quantum Science and Technology, 2018 - iopscience.iop.org
Finding efficient decoders for quantum error correcting codes adapted to realistic
experimental noise in fault-tolerant devices represents a significant challenge. In this paper …

Lattice surgery with a twist: simplifying clifford gates of surface codes

D Litinski, F von Oppen - Quantum, 2018 - quantum-journal.org
We present a planar surface-code-based scheme for fault-tolerant quantum computation
which eliminates the time overhead of single-qubit Clifford gates, and implements long …