Zobrazeno 1 - 10
of 78
pro vyhledávání: '"Lipovský, Jiří"'
Autor:
Freitas, Pedro, Lipovský, Jiří
We derive an expression for the spectral determinant of a second-order elliptic differential operator $\mathcal{T}$ defined on the whole real line, in terms of the Wronskians of two particular solutions of the equation $\mathcal{T} u=0$. Examples of
Externí odkaz:
http://arxiv.org/abs/2405.03469
Autor:
Krejcirik, David, Lipovsky, Jiri
A closed formula for the spectral determinant for the wave equation on a bounded interval, subject to Dirichlet boundary conditions and an $\alpha$-multiple of the Dirac $\delta$-type damping, is derived. Depending on the choice of the branch cut of
Externí odkaz:
http://arxiv.org/abs/2404.11992
Autor:
Lipovský, Jiří, Macháček, Tomáš
The spectral determinant is usually defined using the spectral zeta function that is meromorphically continued to zero. In this definition, the complex logarithms of the eigenvalues appear. Hence the notion of the spectral determinant depends on the
Externí odkaz:
http://arxiv.org/abs/2312.07155
We analyze a square lattice graph in a magnetic field assuming that the vertex coupling is of a particular type violating the time reversal invariance. Calculating the spectrum numerically for rational values of the flux per plaquette we show how the
Externí odkaz:
http://arxiv.org/abs/2302.04601
Autor:
Exner, Pavel, Lipovský, Jiří
Using a technique introduced by Sergei Naboko, we analyze a generalization of the parameter-controlled model of spectral transition, originally proposed by Smilansky and Solomyak, to the situation where the singular interaction responsible for the ef
Externí odkaz:
http://arxiv.org/abs/2207.03713
We discuss spectral properties of an periodic quantum graph consisting of an array of rings coupled either tightly or loosely through connecting links, assuming that the vertex coupling is manifestly non-invariant with respect to the time reversal an
Externí odkaz:
http://arxiv.org/abs/2201.01502
Publikováno v:
Phys. Rev. E 103 (2021), 032208
We investigate experimentally a Fermi golden rule in two-edge and five-edge microwave networks with preserved time reversal invariance. A Fermi golden rule gives rates of decay of states obtained by perturbing embedded eigenvalues of graphs and netwo
Externí odkaz:
http://arxiv.org/abs/2108.05584
Autor:
Ježek, Vladimír, Lipovský, Jiří
We apply the quotient graph theory described by Band, Berkolaiko, Joyner and Liu to particular graphs symmetric with respect to $S_3$ and $C_3$ symmetry groups. We find the quotient graphs for the three-edge star quantum graph with Neumann boundary c
Externí odkaz:
http://arxiv.org/abs/2108.05253
Autor:
Exner, Pavel, Lipovsky, Jiri
We examine quantum transport in periodic quantum graphs with a vertex coupling non-invariant with respect to time reversal. It is shown that the graph topology may play a decisive role in the conductivity properties illustrating this claim with two e
Externí odkaz:
http://arxiv.org/abs/2001.10735