English
Related papers

Related papers: Computation of Green's function by local variation…

200 papers

Time-dependent quantum mechanics provides an intuitive picture of particle propagation in external fields. Semiclassical methods link the classical trajectories of particles with their quantum mechanical propagation. Many analytical results…

Mesoscale and Nanoscale Physics · Physics 2008-03-07 Tobias Kramer , Eric J. Heller , Robert E. Parrott

Quantum computers are the ideal platform for quantum simulations. Given enough coherent operations and qubits, such machines can be leveraged to simulate strongly correlated materials, where intricate quantum effects give rise to…

Quantum Physics · Physics 2016-12-14 Pierre-Luc Dallaire-Demers , Frank K. Wilhelm

We provide fast algorithms for simulating many body Fermi systems on a universal quantum computer. Both first and second quantized descriptions are considered, and the relative computational complexities are determined in each case. In…

Quantum Physics · Physics 2009-10-30 Daniel S. Abrams , Seth Lloyd

An efficient and compact approach to the inclusion of dissipative effects in Non-Equilibrium Green's Function (NEGF) simulations of electronic systems is introduced. The algorithm is based on two well known methods in the literature,…

Mesoscale and Nanoscale Physics · Physics 2018-03-07 Jesse A. Vaitkus , Jared H. Cole

Quantum simulation has shown great potential in many fields due to its powerful computational capabilities. However, the limited fidelity can lead to a severe limitation on the number of gate operations, which requires us to find optimized…

Quantum Physics · Physics 2021-09-20 Yi-Tong Zou , Yu-Jiao Bo , Ji-Chong Yang

We present a massively parallel algorithm for calculating the self-energy in self-consistent finite temperature perturbation theory for lattice models. The algorithm uses analytic functions with appropriate asymptotic high frequency…

Condensed Matter · Physics 2007-05-23 J. J. Deisz , D. W. Hess , J. W. Serene

We propose and demonstrate a unified hierarchical method to measure $n$-point correlation functions that can be applied to driven, dissipative, or otherwise open or non-equilibrium quantum systems. In this method, the time evolution of the…

Quantum Physics · Physics 2024-02-29 Lorenzo Del Re , Brian Rost , Michael Foss-Feig , A. F. Kemper , J. K. Freericks

A quantum Monte Carlo method with non-local update scheme is presented. The method is based on a path-integral decomposition and a worm operator which is local in imaginary time. It generates states with a fixed number of particles and…

Statistical Mechanics · Physics 2009-11-11 Kris Van Houcke , Stefan Rombouts , Lode Pollet

By using the generating function formula for the product of two q-Hermite polynomials q-deformation of the Feynman Green function for the harmonic oscillator is obtained.

q-alg · Mathematics 2009-10-30 H. Ahmedov , I. H. Duru

We outline a strategy to compute deeply inelastic scattering structure functions using a hybrid quantum computer. Our approach takes advantage of the representation of the fermion determinant in the QCD path integral as a quantum mechanical…

High Energy Physics - Theory · Physics 2020-07-22 Niklas Mueller , Andrey Tarasov , Raju Venugopalan

The calculation of dynamic response functions is expected to be an early application benefiting from rapidly developing quantum hardware resources. The ability to calculate real-time quantities of strongly-correlated quantum systems is one…

We introduce a quantum dot orbital tight-binding non-equilibrium Green's function approach for the simulation of novel solar cell devices where both absorption and conduction are mediated by quantum dot states. By the use of basis states…

Mesoscale and Nanoscale Physics · Physics 2012-06-14 U. Aeberhard

We report a linear-scaling random Green's function (rGF) method for large-scale electronic structure calculation. In this method, the rGF is defined on a set of random states to stochastically express the density matrix, and rGF is…

Mesoscale and Nanoscale Physics · Physics 2024-03-05 Mingfa Tang , Chang Liu , Aixia Zhang , Qingyun Zhang , Shengjun Yuan , Youqi Ke

We present two algorithms, one quantum and one classical, for estimating partition functions of quantum spin Hamiltonians. The former is a DQC1 (Deterministic quantum computation with one clean qubit) algorithm, and the first such for…

Quantum Physics · Physics 2023-02-01 Andrew Jackson , Theodoros Kapourniotis , Animesh Datta

A nonperturbative method to obtain on- and off-site one-particle Green's function is introduced and applied to noninteracting Hubbard model with next nearest neighbor hopping and interacting Hubbard model in large dimensions, for example.…

Strongly Correlated Electrons · Physics 2008-02-03 Jongbae Hong

We present a family of algorithms for the numerical approximation of the Schr\"odinger equation with potential concentrated at a finite set of points. Our methods belong to the so-called fast and oblivious convolution quadrature algorithms.…

Numerical Analysis · Mathematics 2019-12-02 Lehel Banjai , María López-Fernández

The quantum circuit model is the de-facto way of designing quantum algorithms. Yet any level of abstraction away from the underlying hardware incurs overhead. In the era of near-term, noisy, intermediate-scale quantum (NISQ) hardware with…

Quantum Physics · Physics 2021-08-27 Laura Clinton , Johannes Bausch , Toby Cubitt

In this work we propose an approach for implementing time-evolution of a quantum system using product formulas. The quantum algorithms we develop have provably better scaling (in terms of gate complexity and circuit depth) than a naive…

We introduce a performance-optimized method to simulate localization problems on bipartite tight-binding lattices. It combines an exact renormalization group step to reduce the sparseness of the original problem with the recursive Green's…

Disordered Systems and Neural Networks · Physics 2021-06-08 Martin Puschmann , Thomas Vojta

We discuss the simulation of a complex dynamical system, the so-called quantum sawtooth map model, on a quantum computer. We show that a quantum computer can be used to efficiently extract relevant physical information for this model. It is…

Quantum Physics · Physics 2007-05-23 Giuliano Benenti , Giulio Casati , Simone Montangero