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Papers

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

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12,928 papers in 12 months (-5% vs prior quarter)

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583 papers found

Sub-system quantum dynamics using coupled cluster downfolding techniques.

K. Kowalski, Nicholas P. Bauman·Mar 21, 2020

In this paper, we discuss extending the sub-system embedding sub-algebra coupled cluster formalism and the double unitary coupled cluster (DUCC) ansatz to the time domain. An important part of the analysis is associated with proving the exactness of ...

PhysicsMedicine

Quantum algorithm for matrix functions by Cauchy's integral formula

S. Takahira, A. Ohashi, T. Sogabe +1 more·Feb 1, 2020

For matrix A, vector b and function f, the computation of vector f(A)b arises in many scientific computing applications. We consider the problem of obtaining quantum state |f> corresponding to vector f(A)b. There is a quantum algorithm to compute sta...

MathematicsComputer SciencePhysics

Symmetry-adapted variational quantum eigensolver

K. Seki, T. Shirakawa, S. Yunoki·Dec 31, 2019

We propose a scheme to restore spatial symmetry of Hamiltonian in the variational-quantum-eigensolver (VQE) algorithm for which the quantum circuit structures used usually break the Hamiltonian symmetry. The symmetry-adapted VQE scheme introduced her...

Physics

Entanglement-Assisted Quantum Codes from Cyclic Codes

F. Pereira·Nov 14, 2019

Entanglement-assisted quantum-error-correcting (EAQEC) codes are quantum codes which use entanglement as a resource. These codes can provide better error correction than the (entanglement unassisted) codes derived from the traditional stabilizer form...

Computer ScienceMedicineMathematicsPhysics

Quantum Linear System Solver Based on Time-optimal Adiabatic Quantum Computing and Quantum Approximate Optimization Algorithm

Dong An, Lin Lin·Sep 12, 2019

We demonstrate that with an optimally tuned scheduling function, adiabatic quantum computing (AQC) can readily solve a quantum linear system problem (QLSP) with O(κ poly(log (κ ε))) runtime, where κ is the condition number, and ε is the target accura...

PhysicsMathematicsComputer Science

Short-depth circuits for efficient expectation-value estimation

A. Roggero, A. Baroni·May 21, 2019

The evaluation of expectation values $Tr\left[\rho O\right]$ for some pure state $\rho$ and Hermitian operator $O$ is of central importance in a variety of quantum algorithms. Near optimal techniques developed in the past require a number of measurem...

Physics

Quantum anomaly detection with density estimation and multivariate Gaussian distribution

Jin‐Min Liang, Shuqian Shen, Ming Li +1 more·May 8, 2019

We study quantum anomaly detection with density estimation and multivariate Gaussian distribution. Both algorithms are constructed using the standard gate-based model of quantum computing. Compared with the corresponding classical algorithms, the res...

MathematicsPhysics

Kerdock Codes Determine Unitary 2-Designs

Trung Can, Narayanan Rengaswamy, R. Calderbank +1 more·Apr 16, 2019

The non-linear binary Kerdock codes are known to be Gray images of certain extended cyclic codes of length <inline-formula> <tex-math notation="LaTeX">$N = 2^{m}$ </tex-math></inline-formula> over <inline-formula> <tex-math notation="LaTeX">$\mathbb ...

Computer ScienceMathematicsPhysics

Quantum algorithm for spectral projection by measuring an ancilla iteratively

Yanzhu Chen, T. Wei·Mar 28, 2019

We propose a quantum algorithm for projecting to eigenstates of any hermitian operator, provided one can access the associated control-unitary evolution and measurement of the ancilla of the control. The procedure is iterative and the distribution of...

PhysicsMathematics

Universal variational quantum computation

J. Biamonte·Mar 11, 2019

Variational quantum algorithms dominate contemporary gate-based quantum enhanced optimisation [1], eigenvalue estimation [2] and machine learning [3]. Here we establish the quantum computational universality of variational quantum computation by deve...

PhysicsMathematics

An Improved Algorithm for Quantum Principal Component Analysis.

Changpeng Shao·Mar 10, 2019

Principal component analysis is an important dimension reduction technique in machine learning. In [S. Lloyd, M. Mohseni and P. Rebentrost, Nature Physics 10, 631-633, (2014)], a quantum algorithm to implement principal component analysis on quantum ...

Physics

Downfolding of many-body Hamiltonians using active-space models: Extension of the sub-system embedding sub-algebras approach to unitary coupled cluster formalisms.

Nicholas P. Bauman, E. Bylaska, S. Krishnamoorthy +6 more·Feb 5, 2019

In this paper, we discuss the extension of the recently introduced subsystem embedding subalgebra coupled cluster (SES-CC) formalism to unitary CC formalisms. In analogy to the standard single-reference SES-CC formalism, its unitary CC extension allo...

PhysicsMathematicsMedicine

Quantum-inspired classical sublinear-time algorithm for solving low-rank semidefinite programming via sampling approaches

Nai-Hui Chia, Tongyang Li, Han-Hsuan Lin +1 more·Jan 10, 2019

Semidefinite programming (SDP) is a central topic in mathematical optimization with extensive studies on its efficient solvers. Recently, quantum algorithms with superpolynomial speedups for solving SDPs have been proposed assuming access to its cons...

MathematicsComputer SciencePhysics

Variational Quantum Simulation of General Processes.

Suguru Endo, Jinzhao Sun, Y. Li +2 more·Dec 20, 2018

Variational quantum algorithms have been proposed to solve static and dynamic problems of closed many-body quantum systems. Here we investigate variational quantum simulation of three general types of tasks-generalized time evolution with a non-Hermi...

PhysicsMathematicsMedicine

VanQver: the variational and adiabatically navigated quantum eigensolver

S. Matsuura, T. Yamazaki, Valentin Senicourt +2 more·Oct 26, 2018

The accelerated progress in manufacturing noisy, intermediate-scale quantum (NISQ) computing hardware has opened the possibility of exploring its application in transforming approaches to solving computationally challenging problems. The important li...

Physics

Jointly Constrained Semidefinite Bilinear Programming With an Application to Dobrushin Curves

Stefan Huber, R. König, M. Tomamichel·Aug 9, 2018

We propose a branch-and-bound algorithm for minimizing a bilinear functional of the form <inline-formula> <tex-math notation="LaTeX">$f(X,Y) = \mathrm {tr}((X\otimes Y)Q)+ \mathrm {tr}(AX)+ \mathrm {tr}(BY) $ </tex-math></inline-formula>, of pairs of...

PhysicsMathematicsComputer Science

Hamiltonian surgery: Cheeger-type gap inequalities for nonpositive (stoquastic), real, and Hermitian matrices

Michael Jarret·Apr 18, 2018

Cheeger inequalities bound the spectral gap $\gamma$ of a space by isoperimetric properties of that space and vice versa. In this paper, I derive Cheeger-type inequalities for nonpositive matrices (aka stoquastic Hamiltonians), real matrices, and Her...

MathematicsPhysics

Approximating Hamiltonian dynamics with the Nyström method

Alessandro Rudi, Leonard Wossnig, C. Ciliberto +3 more·Apr 6, 2018

Simulating the time-evolution of quantum mechanical systems is BQP-hard and expected to be one of the foremost applications of quantum computers. We consider classical algorithms for the approximation of Hamiltonian dynamics using subsampling methods...

MathematicsPhysicsComputer Science

Quantum algorithms for training Gaussian Processes

Zhikuan Zhao, Jack K. Fitzsimons, Michael A. Osborne +2 more·Mar 28, 2018

Gaussian processes (GPs) are important models in supervised machine learning. Training in Gaussian processes refers to selecting the covariance functions and the associated parameters in order to improve the outcome of predictions, the core of which ...

PhysicsComputer ScienceMathematics

Quantum Algorithms to Matrix Multiplication

Changpeng Shao·Mar 5, 2018

In this paper, we study quantum algorithms of matrix multiplication from the viewpoint of inputting quantum/classical data to outputting quantum/classical data. The main target is trying to overcome the input and output problem, which are not easy to...

PhysicsMathematics
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