Quantum Brain

Papers

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

Total Papers

31,714

This Month

152

Today

0

Research Volume

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

Research Focus Areas

Papers by research theme (12 months). Hover for details.

Qubit Platforms

Hardware platform mentions in abstractsPhotonic leads

31,714 papers found

Regimes of Classical Simulability for Noisy Gaussian Boson Sampling.

H. Qi, D. Brod, N. Quesada +1 more·May 29, 2019

As a promising candidate for exhibiting quantum computational supremacy, Gaussian boson sampling (GBS) is designed to exploit the ease of experimental preparation of Gaussian states. However, sufficiently large and inevitable experimental noise might...

MedicinePhysics

Protecting quantum entanglement from leakage and qubit errors via repetitive parity measurements

C. C. Bultink, T. O’Brien, R. Vollmer +9 more·May 29, 2019

We protect two-transmon entanglement from qubit leakage using the same parity checks used to correct standard qubit errors. Protecting quantum information from errors is essential for large-scale quantum computation. Quantum error correction (QEC) en...

Computer ScienceMedicineMathematicsPhysics

Optimizing QAOA: Success Probability and Runtime Dependence on Circuit Depth

M. Niu, Sirui Lu, I. Chuang·May 28, 2019

The quantum approximate optimization algorithm~(QAOA) first proposed by Farhi et al. promises near-term applications based on its simplicity, universality, and provable optimality. A depth-p QAOA consists of p interleaved unitary transformations indu...

MathematicsPhysics

Row and column iteration methods to solve linear systems on a quantum computer

Changpeng Shao, Hua Xiang·May 28, 2019

We consider the quantum implementations of the two classical iterative solvers for a system of linear equations, including the Kaczmarz method which uses a row of coefficient matrix in each iteration step, and the coordinate descent method which util...

PhysicsMathematics

Defining Quantum Neural Networks via Quantum Time Evolution

Aditya Dendukuri, B. Keeling, A. Fereidouni +3 more·May 27, 2019

This work presents a novel fundamental algorithm for for defining and training Neural Networks in Quantum Information based on time evolution and the Hamiltonian. Classical Neural Network algorithms (ANN) are computationally expensive. For example, i...

Computer SciencePhysicsMathematics

Full-Stack, Real-System Quantum Computer Studies: Architectural Comparisons and Design Insights

Prakash Murali, N. Linke, M. Martonosi +3 more·May 27, 2019

In recent years, Quantum Computing (QC) has progressed to the point where small working prototypes are available for use. Termed Noisy Intermediate-Scale Quantum (NISQ) computers, these prototypes are too small for large benchmarks or even for Quantu...

PhysicsComputer Science

Distinguishing noisy boson sampling from classical simulations

V. Shchesnovich·May 27, 2019

Giving a convincing experimental evidence of the quantum supremacy over classical simulations is a challenging goal. Noise is considered to be the main problem in such a demonstration, hence it is urgent to understand the effect of noise. Recently fo...

Computer SciencePhysics

Four electron spin qubits with exchange interaction

H. Naus·May 27, 2019

Four electron spin qubits in quantum dots are studied by means of an exchange interaction Hamiltonian. The time-independent Schr¨odinger equation is exactly analytically solved for the symmetric case, that is equal qubit frequencies and equal couplin...

PhysicsMathematics

Dynamics of charge-resolved entanglement after a local quench

Noa Feldman, M. Goldstein·May 26, 2019

Quantum entanglement and its main quantitative measures, the entanglement entropy and entanglement negativity, play a central role in many body physics. An interesting twist arises when the system considered has symmetries leading to conserved quanti...

Physics

Empirical determination of the simulation capacity of a near-term quantum computer

Rich Rines, K. Obenland, I. Chuang·May 26, 2019

Experimentally realizable quantum computers are rapidly approaching the threshold of quantum supremacy. Quantum Hamiltonian simulation promises to be one of the first practical applications for which such a device could demonstrate an advantage over ...

PhysicsMathematics

Expressibility and Entangling Capability of Parameterized Quantum Circuits for Hybrid Quantum‐Classical Algorithms

Sukin Sim, Peter D. Johnson, Alán Aspuru-Guzik·May 26, 2019

Parameterized quantum circuits (PQCs) play an essential role in the performance of many variational quantum algorithms. One challenge in implementing such algorithms is choosing an effective circuit that well represents the solution space while maint...

Computer SciencePhysics

Error correction schemes for fully correlated quantum channels protecting both quantum and classical information

Chi-Kwong Li, Seth Lyles, Y. Poon·May 24, 2019

We study efficient quantum error correction schemes for the fully correlated channel on an n-qubit system with error operators that assume the form σx⊗n\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \use...

PhysicsComputer Science

Computing scalar products via a two-terminal quantum transmission line

J. Stolze, A. Zenchuk·May 24, 2019

The scalar product of two vectors with $K$ real components can be computed using two quantum channels, that is, information transmission lines in the form of spin-1/2 XX chains. Each channel has its own $K$-qubit sender and both channels share a sing...

Physics

Error-mitigated quantum gates exceeding physical fidelities in a trapped-ion system

Shuaining Zhang, Yao Lu, Kuan Zhang +4 more·May 24, 2019

Various quantum applications can be reduced to estimating expectation values, which are inevitably deviated by operational and environmental errors. Although errors can be tackled by quantum error correction, the overheads are far from being affordab...

MedicineComputer ScienceBiologyPhysics

Quantum-inspired algorithms in practice

J. Arrazola, A. Delgado, Bhaskar Roy Bardhan +1 more·May 24, 2019

We study the practical performance of quantum-inspired algorithms for recommendation systems and linear systems of equations. These algorithms were shown to have an exponential asymptotic speedup compared to previously known classical methods for pro...

Computer SciencePhysics

Asymptotic Improvements to Quantum Circuits via Qutrits

P. Gokhale, Jonathan M. Baker, Casey Duckering +3 more·May 24, 2019

Quantum computation is traditionally expressed in terms of quantum bits, or qubits. In this work, we instead consider three-level qutrits. Past work with qutrits has demonstrated only constant factor improvements, owing to the $\log_{2}$ (3) binary-t...

MathematicsComputer SciencePhysics

Quantum Circuits for Dynamic Runtime Assertions in Quantum Computation

Huiyang Zhou, Gregory T. Byrd·May 24, 2019

In this paper, we propose quantum circuits for runtime assertions, which can be used for both software debugging and error detection. Runtime assertion is challenging in quantum computing for two key reasons. First, a quantum bit (qubit) cannot be co...

Computer SciencePhysics

Quantum Period Finding with a Single Output Qubit - Factoring n-bit RSA with n/2 Qubits

Alexander May, Lars Schlieper·May 24, 2019

We study quantum period finding algorithms such as Simon, Shor, and Ekera-Hastad. For a periodic function $f$ these algorithms produce -- via some quantum embedding of $f$ -- a quantum superposition $\sum_x \vert x\rangle\vert f(x)\rangle$, which req...

Computer SciencePhysics

How to factor 2048 bit RSA integers in 8 hours using 20 million noisy qubits

C. Gidney, Martin Ekerå·May 23, 2019

We significantly reduce the cost of factoring integers and computing discrete logarithms in finite fields on a quantum computer by combining techniques from Shor 1994, Griffiths-Niu 1996, Zalka 2006, Fowler 2012, Ekerå-Håstad 2017, Ekerå 2017, Ekerå ...

MathematicsPhysicsComputer Science

Revisiting Shor's quantum algorithm for computing general discrete logarithms

Martin Ekerå·May 22, 2019

We heuristically show that Shor's algorithm for computing general discrete logarithms achieves an expected success probability of approximately 60% to 82% in a single run when modified to enable efficient implementation with the semi-classical Fourie...

CryptographyQuantum Physics
Quantum Intelligence

Ask about quantum research, companies, or market developments.