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Related papers: Quantum graphs with spin Hamiltonians

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The regular structures obtained by optical lattice technology and their behaviour are analysed from the quantum information perspective. Initially, we demonstrate that a triangular optical lattice of two atomic species, bosonic or…

The Schr\" odinger picture of the Dirac quantum mechanics is defined in charts with spatially flat Robertson-Walker metrics and Cartesian coordinates. The main observables of this picture are identified, including the interacting part of…

General Relativity and Quantum Cosmology · Physics 2014-10-07 Ion I. Cotaescu

This is the second paper in the series to introduce a graphical method to loop quantum gravity. We employ the graphical method as a powerful tool to calculate the actions of the Euclidean Hamiltonian constraint operator and the so-called…

General Relativity and Quantum Cosmology · Physics 2016-02-25 Jinsong Yang , Yongge Ma

We study the spectral properties of a spin-boson Hamiltonian that depends on two continuous parameters $0\leq\Lambda<\infty$ (interaction strength) and $0\leq\alpha\leq\pi/2$ (integrability switch). In the classical limit this system has…

Other Condensed Matter · Physics 2009-11-13 Vyacheslav V. Stepanov , Gerhard Muller , Joachim Stolze

A path integral method, combined with atomistic spin dynamics simulations, has been developed to calculate thermal quantum expectation values using a classical approach. In this study, we show how to treat Hamiltonians with non-linear…

Quantum Physics · Physics 2024-08-12 Thomas Nussle , Pascal Thibaudeau , Stam Nicolis

Here I present a new discrete model of quantum mechanics for relativistic 1-electron systems, in which particle movement is described by a directed space-time graph with attached 4-spinors, but without any continuous wave functions. These…

Quantum Physics · Physics 2007-05-23 Wolfgang Koehler

A quantum computing circuit is presented that approximates a single spin wave quantum on a linear chain of spin 1/2 particles described by a Heisenberg Hamiltonian. The circuit is a product state where each qubit represents a spin. The spin…

Quantum Physics · Physics 2025-07-31 Daniel D. Stancil , Bojko N. Bakalov , Gregory T. Byrd

We propose a method for the tomographic reconstruction of qubit states for a general class of solid state systems in which the Hamiltonians are represented by spin operators, e.g., with Heisenberg-, $XXZ$-, or XY- type exchange…

Quantum Physics · Physics 2009-11-10 Yu-xi Liu , L. F. Wei , Franco Nori

A set of Pauli stings is well characterized by the graph that encodes its commutatitivity structure, i.e., by its frustration graph. This graph provides a natural interface between graph theory and quantum information, which we explore in…

Quantum Physics · Physics 2025-11-18 Zhen-Peng Xu , Jie Wang , Qi Ye , Gereon Koßmann , René Schwonnek , Andreas Winter

Inspired by the spin geometry theorem, two operators are defined which measure angles in the quantum theory of geometry. One operator assigns a discrete angle to every pair of surfaces passing through a single vertex of a spin network. This…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Seth A. Major

The spectral properties of the Laplacian on a class of quantum graphs with random metric structure are studied. Namely, we consider quantum graphs spanned by the simple $\ZZ^d$-lattice with $\delta$-type boundary conditions at the vertices,…

Mathematical Physics · Physics 2009-11-13 Frédéric Klopp , Konstantin Pankrashkin

Several topics on the implementation of spin qubits in quantum dots are reviewed. We first provide an introduction to the standard model of quantum computing and the basic criteria for its realization. Other alternative formulations such as…

Mesoscale and Nanoscale Physics · Physics 2010-07-20 Robert Andrzej Żak , Beat Röthlisberger , Stefano Chesi , Daniel Loss

Spinors have played an essential but enigmatic role in modern physics since their discovery. Now that quantum-gravitational theories have started to become available, the inclusion of a description of spin in the development is natural and…

Mathematical Physics · Physics 2007-05-23 Daniel C. Galehouse

We derive an explicit Hamiltonian for copying the basis up and down states of a quantum two-state system - a qubit - onto n "copy" qubits initially all prepared in the down state. In terms of spin components, for spin-1/2 particle spin…

Quantum Physics · Physics 2014-11-18 Dima Mozyrsky , Vladimir Privman , Mark Hillery

In canonical quantum gravity, when space is a compact manifold with boundary there is a Hamiltonian given by an integral over the boundary. Here we compute the action of this `boundary Hamiltonian' on observables corresponding to open…

General Relativity and Quantum Cosmology · Physics 2009-10-28 John Baez , Javier P. Muniain , Dardo Piriz

Circuit quantization is an extraordinarily successful theory that describes the behavior of quantum circuits with high precision. The most widely used approach of circuit quantization relies on introducing a classical Lagrangian whose…

Quantum Physics · Physics 2024-04-12 Andrew Osborne , Trevyn Larson , Sarah Jones , Ray W. Simmonds , András Gyenis , Andrew Lucas

We consider the question of what quantum spin chains naturally encode in their Hilbert space. It turns out that quantum spin chains are rather rich systems, naturally encoding solutions to various problems in combinatorics, group theory,…

Quantum Physics · Physics 2024-07-24 Marcos Crichigno , Anupam Prakash

We study Schr\"odinger operators on compact finite metric graphs subject to $\delta$-coupling and standard boundary conditions. We compare the $n$-th eigenvalues of those self-adjoint realizations and derive an asymptotic result for the…

Mathematical Physics · Physics 2023-09-06 Patrizio Bifulco , Joachim Kerner

We discuss the formulation of spin observables associated to a non-relativistic spinning particles in terms of grassmanian differential operators. We use as configuration space variables for the pseudo-classical description of this system…

High Energy Physics - Theory · Physics 2007-05-23 J. A. Lopez , J. Stephany

We consider a relativistic superalgebra in the picture in which the time and spatial derivative cannot be presented in the operators of the particle. The supersymmetry generators as well as the Hamilton operators for the massive…

High Energy Physics - Theory · Physics 2011-09-13 Rudolf A. Frick