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Papers

Live trends in quantum computing research, updated daily from arXiv.

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31,714

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15,746 papers in 12 months (-37% vs prior quarter)

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Qubit Platforms

Hardware platform mentions in abstractsPhotonic leads

31,714 papers found

Phase Gadget Synthesis for Shallow Circuits

Alexander Cowtan, Silas Dilkes, Ross Duncan +2 more·Jun 4, 2019

We give an overview of the circuit optimisation methods used by tket, a compiler system for quantum software developed by Cambridge Quantum Computing Ltd. We focus on a novel technique based around phase gadgets, a family of multi-qubit quantum opera...

Computer SciencePhysics

Fidelity deviation in quantum teleportation with a two-qubit state

Arkaprabha Ghosal, D. Das, Saptarshi Roy +1 more·Jun 4, 2019

Quantum teleportation with an arbitrary two-qubit state can be appropriately characterized in terms of maximal fidelity and fidelity deviation. The former quantifies optimality of the process and is defined as the maximal average fidelity achievable ...

PhysicsMathematics

Quantum algorithm for total least squares data fitting

Hefeng Wang, Hua Xiang·Jun 4, 2019

Abstract The total least squares (TLS) method is widely used in data-fitting. Compared with the least squares fitting method, the TLS fitting takes into account not only observation errors, but also errors from the measurement matrix of the variables...

Physics

Convolution filter embedded quantum gate autoencoder

Kodai Shiba, K. Sakamoto, Koichi Yamaguchi +2 more·Jun 4, 2019

The autoencoder is one of machine learning algorithms used for feature extraction by dimension reduction of input data, denoising of images, and prior learning of neural networks. At the same time, autoencoders using quantum computers are also being ...

PhysicsComputer Science

Perturbative calculation of field space entanglement entropy

James Brister·Jun 3, 2019

We present a general method for the perturbative calculation of the entanglement entropy between two interacting quantum fields. Previous attempts at calculating this quantity perturbatively have encountered a seemingly pathological divergence; we ex...

hep-thQuantum Physics

Coherent electrical control of a single high-spin nucleus in silicon

Serwan Asaad, V. Mourik, Benjamin Joecker +12 more·Jun 3, 2019

Nuclear spins are highly coherent quantum objects. In large ensembles, their control and detection via magnetic resonance is widely exploited, for example, in chemistry, medicine, materials science and mining. Nuclear spins also featured in early pro...

PhysicsMedicineMaterials Science

Hamiltonian engineering of general two-body spin-1/2 interactions

K. Attar, D. Farfurnik, N. Bar-Gill·Jun 2, 2019

Spin Hamiltonian engineering in solid-state systems plays a key role in a variety of applications ranging from quantum information processing and quantum simulations to novel studies of many-body physics. By analyzing the irreducible form of a genera...

Physics

Noise reduction using past causal cones in variational quantum algorithms

Omar Shehab, Isaac H. Kim, N. Nguyen +5 more·Jun 2, 2019

We introduce an approach to improve the accuracy and reduce the sample complexity of near term quantum-classical algorithms. We construct a simpler initial parameterized quantum state, or ansatz, based on the past causal cone of each observable, gene...

Computer SciencePhysicsMathematics

Microwave Packaging for Superconducting Qubits

Benjamin Lienhard, Jochen Braumuller, W. Woods +8 more·Jun 1, 2019

Over the past two decades, the performance of superconducting quantum circuits has tremendously improved. The progress of superconducting qubits enabled a new industry branch to emerge from global technology enterprises to quantum computing startups....

Physics

Experimental Demonstration of Force Driven Quantum Harmonic Oscillator in IBM Quantum Computer.

A. Baishya, L. Kumar, B. K. Behera +1 more·Jun 1, 2019

Though algorithms for quantum simulation of Quantum Harmonic Oscillator (QHO) have been proposed, still they have not yet been experimentally verified. Here, for the first time, we demonstrate a quantum simulation of QHO in the presence of both time-...

MathematicsPhysics

Thermo Field Dynamics on a Quantum Computer

R. Miceli, M. McGuigan·Jun 1, 2019

In this project we develop a quantum algorithm to realize finite temperature simulation on a quantum computer. As quantum computers use real-time evolution we did not use the imaginary time methods popular on classical algorithms. Instead, we impleme...

Physics

Quantum-inspired memory-enhanced stochastic algorithms

John Realpe-G'omez, N. Killoran·Jun 1, 2019

Stochastic models are highly relevant tools in science, engineering, and society. Recent work suggests emerging quantum computing technologies can substantially decrease the memory requirements for simulating stochastic models. Here we show that some...

PhysicsComputer Science

Long-step path-following algorithm for quantum information theory: Some numerical aspects and applications

L. Faybusovich, Cunlu Zhou·May 31, 2019

We consider some important computational aspects of the long-step path-following algorithm developed in our previous work and show that a broad class of complicated optimization problems arising in quantum information theory can be solved using this ...

Computer ScienceMathematics

Experimental test of non-macrorealistic cat states in the cloud

Huan-Yu Ku, Neill Lambert, Feng-Jui Chan +3 more·May 31, 2019

The Leggett–Garg inequality attempts to classify experimental outcomes as arising from one of two possible classes of physical theories: those described by macrorealism (which obey our intuition about how the macroscopic classical world behaves) and ...

PhysicsEnvironmental Science

Revisiting the behavior of quantum correlations under nondissipative decoherence by means of the correlation matrix

D. Bussandri, T. M. Os'an, A. P. Majtey +13 more·May 31, 2019

In this paper we use the Fano representation of two-qubit states from which we can identify a correlation matrix containing the information about the classical and quantum correlations present in the bipartite quantum state. To illustrate the use of ...

Physics

Superconducting Qubits: Current State of Play

M. Kjaergaard, M. Schwartz, Jochen Braumuller +4 more·May 31, 2019

Superconducting qubits are leading candidates in the race to build a quantum computer capable of realizing computations beyond the reach of modern supercomputers. The superconducting qubit modality has been used to demonstrate prototype algorithms in...

PhysicsComputer Science

On Post-Processing the Results of Quantum Optimizers

Ajinkya Borle, Josh McCarter·May 30, 2019

The use of quantum computing for applications involving optimization has been regarded as one of the areas it may prove to be advantageous (against classical computation). To further improve the quality of the solutions, post-processing techniques ar...

Computer SciencePhysics

Dual-species, multi-qubit logic primitives for Ca+/Sr+ trapped-ion crystals

C. Bruzewicz, R. McConnell, J. Stuart +2 more·May 30, 2019

We demonstrate key multi-qubit quantum-logic primitives in a dual-species trapped-ion system based on $${}^{40}$$40Ca$${}^{+}$$+ and $${}^{88}$$88Sr$${}^{+}$$+ ions, using two optical qubits with quantum-logic-control frequencies in the red to near-i...

PhysicsMathematics

Qubit regularization of the O(3) sigma model

Hersh Singh, S. Chandrasekharan·May 30, 2019

We construct a qubit regularization of the $O(3)$ non-linear sigma model in two and three spatial dimensions using a quantum Hamiltonian with two qubits per lattice site. Using a worldline formulation and worm algorithms, we show that in two spatial ...

Physics

Experimental Hamiltonian Learning of an 11-Qubit Solid-State Quantum Spin Register*

P. Hou, L. He, F. Wang +7 more·May 29, 2019

Learning Hamiltonian of a quantum system is indispensable for prediction of the system dynamics and realization of high fidelity quantum gates. However, it is a significant challenge to efficiently characterize the Hamiltonian when its Hilbert space ...

PhysicsMathematics
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