English
Related papers

Related papers: Jacobi matrices that realize perfect quantum state…

200 papers

We start from a discussion of the general form and general CP-- and CPT-- transformation properties of the Lee--Oehme--Yang (LOY) effective Hamiltonian for the neutral kaon complex. Next we show that there exists an approximation which is…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Urbanowski

We present a hybrid quantum-classical algorithm to simulate thermal states of a classical Hamiltonians on a quantum computer. Our scheme employs a sequence of locally controlled rotations, building up the desired state by adding qubits one…

Quantum Physics · Physics 2015-03-17 Man-Hong Yung , Daniel Nagaj , James D. Whitfield , Alán Aspuru-Guzik

We show a perfect state transfer of an arbitrary unknown two-qubit state can be achieved via a discrete-time quantum walk with various settings of coin flippings, and extend this method to distribution of an arbitrary unknown multi-qubit…

Quantum Physics · Physics 2014-07-23 Xiang Zhan , Hao Qin , Zhi-hao Bian , Jian Li , Peng Xue

Hamiltonian truncation is a non-perturbative numerical method for calculating observables of a quantum field theory. The starting point for this method is to truncate the interacting Hamiltonian to a finite-dimensional space of states…

High Energy Physics - Theory · Physics 2022-08-10 Timothy Cohen , Kara Farnsworth , Rachel Houtz , Markus A. Luty

The evolution speed in projective Hilbert space is considered for Hermitian Hamiltonians and for non-Hermitian (NH) ones. Based on the Hilbert-Schmidt norm and the spectral norm of a Hamiltonian, resource-related upper bounds on the…

Quantum Physics · Physics 2012-10-02 Raam Uzdin , Uwe Guenther , Saar Rahav , Nimrod Moiseyev

We consider the geometry of quantum states associated with different classes of random matrix Hamiltonians, in particular ensembles that show integrability to chaotic transition in terms of the nearest neighbour energy level spacing…

Quantum Physics · Physics 2025-09-03 Ankit Gill , Keun-Young Kim , Kunal Pal , Kuntal Pal

Quantum state manipulation with gates based on geometric phases acquired during cyclic operations promises inherent fault-tolerance and resilience to local fluctuations in the control parameters. Here we create a general non-Abelian and…

Quantum Physics · Physics 2018-04-06 S. Danilin , A. Vepsäläinen , G. S. Paraoanu

The dynamical evolution of an open quantum system can be governed by the Lindblad equation of the density matrix. In this paper, we propose to characterize the density matrix topology by the topological invariant of its modular Hamiltonian.…

Mesoscale and Nanoscale Physics · Physics 2024-06-27 Liang Mao , Fan Yang , Hui Zhai

Pure states correspond to one-dimensional subspaces of $\mathbb{C}^n$ represented by unit vectors. In this paper, we develop the theory of perfect state transfer (PST) between real pure states with emphasis on the adjacency and Laplacian…

Quantum Physics · Physics 2025-06-13 Chris Godsil , Stephen Kirkland , Hermie Monterde

It is shown that for a given Hermitian Hamiltonian possessing supersymmetry, there is alwayas a non-hermitian Jaynes-Cummings-type Hamiltonian(JCTH) admitting entirely real spectra. The parent supersymmetric Hamiltonian and the…

Quantum Physics · Physics 2009-11-11 Pijush K. Ghosh

The construction of exactly-solvable models has recently been advanced by considering integrable $T\bar{T}$ deformations and related Hamiltonian deformations in quantum mechanics. We introduce a broader class of non-Hermitian Hamiltonian…

High Energy Physics - Theory · Physics 2023-01-18 Apollonas S. Matsoukas-Roubeas , Federico Roccati , Julien Cornelius , Zhenyu Xu , Aurelia Chenu , Adolfo del Campo

Recently Bender, Brody, Jones and Meister found that in the quantum brachistochrone problem the passage time needed for the evolution of certain initial states into specified final states can be made arbitrarily small, when the…

Quantum Physics · Physics 2008-11-26 Paulo E. G. Assis , Andreas Fring

Functional relations among the fusion hierarchy of quantum transfer matrices give a novel derivation of the TBA equations, namely without string hypothesis. This is demonstrated for two important models of 1D highly correlated electron…

High Energy Physics - Theory · Physics 2009-09-25 G. Juettner , A. Kluemper , J. Suzuki

We show that a Dicke-type pseudo-hermitian Hamiltonian undergoes quantum phase transition by mapping it to the "Dressed Dicke Model" through a similarity transformation. We find the positive-definite metric in the Hilbert space of the…

Quantum Physics · Physics 2009-08-14 Tetsuo Deguchi , Pijush K. Ghosh

We present a procedure for exactly diagonalizing finite-range quadratic fermionic Hamiltonians with arbitrary boundary conditions in one of D dimensions, and periodic in the remaining D-1. The key is a Hamiltonian-dependent separation of…

Superconductivity · Physics 2016-10-27 Abhijeet Alase , Emilio Cobanera , Gerardo Ortiz , Lorenza Viola

It is known that for multi-level time-dependent quantum systems one can construct superadiabatic representations in which the coupling between separated levels is exponentially small in the adiabatic limit. For a family of two-state systems…

Mathematical Physics · Physics 2009-11-10 Volker Betz , Stefan Teufel

In this paper we propose a systematic method to solve the inverse dynamical problem for a quantum system governed by the von Neumann equation: to find a class of Hamiltonians reproducing a prescribed time evolution of a pure or mixed state…

Quantum Physics · Physics 2013-07-09 J Bernatska , A Messina

Effective state transfer is one of the most important problems in quantum information processing. Typically, a quantum information device is composed of many subsystems with multi-input ports. In this paper, we develop a general theory…

Quantum Physics · Physics 2016-08-23 Naoki Yamamoto , Hendra I. Nurdin , Matthew R. James

We use projection methods to construct (global) quantum states with prescribed reduced (marginal) states, and possibly with some special properties such as having specific eigenvalues, having specific rank and extreme von Neumann or Renyi…

Quantum Physics · Physics 2020-09-22 Xuefeng Duan , Chi-Kwong Li , Diane Christine Pelejo

What is the quantum state of the universe? Although there have been several interesting suggestions, the question remains open. In this paper, I consider a natural choice for the universal quantum state arising from the Past Hypothesis, a…

Quantum Physics · Physics 2019-01-25 Eddy Keming Chen