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Related papers: Boundary condition at the junction

200 papers

This workshop brought together experts in classical graph theory and quantum information science to explore the intersection of these fields, with a focus on quantum graph states and their applications in computing, networking, and sensing.…

We introduce the concept of regular quantum graphs and construct connected quantum graphs with discrete symmetries. The method is based on a decomposition of the quantum propagator in terms of permutation matrices which control the way…

Chaotic Dynamics · Physics 2007-06-13 Simone Severini , Gregor Tanner

Boundary conditions in quantum graph vertices are generally given in terms of a unitary matrix $U$. Observing that if $U$ has at most two eigenvalues, then the scattering matrix $\mathcal{S}(k)$ of the vertex is a linear combination of the…

Mathematical Physics · Physics 2011-10-06 Ondřej Turek , Taksu Cheon

Quantum network is fragile to disturbances when qubits are transmitted through quantum channel. Reliability is an essential requirement for a quantum network and even the future quantum internet. A metric is needed to describe the…

Quantum Physics · Physics 2020-04-27 Ying Liu

The quantum circuit model is the most widely used model of quantum computation. It provides both a framework for formulating quantum algorithms and an architecture for the physical construction of quantum computers. However, several other…

Quantum Physics · Physics 2008-09-16 Stephen P. Jordan

We consider the Dirac equation on periodic networks (quantum graphs). The self-adjoint quasi periodic boundary conditions are derived. The secular equation allowing us to find the energy spectrum of the Dirac particles on periodic quantum…

Quantum Physics · Physics 2021-08-11 J. R. Yusupov , K. K. Sabirov , D. U. Matrasulov

Quantum graphs are a paradigmatic model for quantum chaos as well as for spectral theory. We give a concise didactical introduction to quantum graphs, or Schr\"odinger Hamiltonians on metric graphs, with a focus on results related to…

Quantum Physics · Physics 2026-05-07 Gregory Berkolaiko , Sven Gnutzmann

In the broad range of studies related to quantum graphs, quantum graph spectra appear as a topic of special interest. They are important in the context of diffusion type problems posed on metric graphs. Theoretical findings suggest that…

Numerical Analysis · Mathematics 2023-12-15 Chong-Son Dröge , Anna Weller

We introduce a broad class of equations that are described by a graph, which includes many well-studied systems. For these, we show that the number of solutions (or the dimension of the solution set) can be bounded by studying certain…

Combinatorics · Mathematics 2024-10-10 Eddie Nijholt , Davide Sclosa

This paper treats a quantum network from a physical approach, explicitly finds the physical eigenstates and compares them to the quantum-graph description. The basic building block of a quantum network is an X-shaped potential well made by…

Mesoscale and Nanoscale Physics · Physics 2018-04-18 Molte Emil Strange Andersen , Nikolaj Thomas Zinner

Quantum theory has shown its superiority in enhancing machine learning. However, facilitating quantum theory to enhance graph learning is in its infancy. This survey investigates the current advances in quantum graph learning (QGL) from…

Machine Learning · Computer Science 2023-02-03 Shuo Yu , Ciyuan Peng , Yingbo Wang , Ahsan Shehzad , Feng Xia , Edwin R. Hancock

A finite dimensional operator that commutes with some symmetry group admits quotient operators, which are determined by the choice of associated representation. Taking the quotient isolates the part of the spectrum supporting the chosen…

Mathematical Physics · Physics 2023-11-30 Ram Band , Gregory Berkolaiko , Christopher H. Joyner , Wen Liu

Choice models for populations of agents on graphs are studied in terms of statistical thermodynamics. Equations of state are derived and discussed for different connectivity schemes, utility approximations, and temperature and volume…

Statistical Mechanics · Physics 2009-09-29 A. Majka , W. Wislicki

A finite discrete graph is turned into a quantum (metric) graph once a finite length is assigned to each edge and the one-dimensional Laplacian is taken to be the operator. We study the dependence of the spectral gap (the first positive…

Mathematical Physics · Physics 2018-03-28 Ram Band , Guillaume Lévy

Quantum computing (QC) is a new computational paradigm whose foundations relate to quantum physics. Notable progress has been made, driving the birth of a series of quantum-based algorithms that take advantage of quantum computational…

Quantum Physics · Physics 2022-02-22 Yehui Tang , Junchi Yan , Hancock Edwin

We present quantum complexity lower and upper bounds for independent set problems in graphs. In particular, we give quantum algorithms for computing a maximal and a maximum independent set in a graph. We present applications of these…

Quantum Physics · Physics 2007-05-23 Sebastian Doern

A major application of the mathematical concept of graph in quantum mechanics is to model networks of electrical wires or electromagnetic wave-guides. In this paper, we address the dynamics of a particle trapped on such a network in…

Optimization and Control · Mathematics 2023-04-19 Alessandro Duca

An alternative model to describe the electronic and thermal properties of quantum dot based on triangle geometry is proposed. The model predicts characteristics and limitations of the system by controlling the magnetic field and…

Mesoscale and Nanoscale Physics · Physics 2023-02-10 Francisco A. G. de Lira , Edilberto O. Silva

Networks constitute efficient tools for assessing universal features of complex systems. In physical contexts, classical as well as quantum, networks are used to describe a wide range of phenomena, such as phase transitions, intricate…

Quantum Physics · Physics 2016-01-22 Jaroslav Novotný , Gernot Alber , Igor Jex

We demonstrate that a quantum graph exhibits a $\mathcal{PT}$-symmetry provided the coefficients in the condition describing the wave function matching at the vertices are circulant matrices; this symmetry is nontrivial if they are not…

Mathematical Physics · Physics 2021-10-04 Pavel Exner , Milos Tater