Dynamical formulation of low-frequency scattering in two and three dimensions
- URL: http://arxiv.org/abs/2410.16906v1
- Date: Tue, 22 Oct 2024 11:26:58 GMT
- Title: Dynamical formulation of low-frequency scattering in two and three dimensions
- Authors: Farhang Loran, Ali Mostafazadeh,
- Abstract summary: Theory of scattering in one dimension can be expressed in terms of the time-evolution operator for an effective non-unitary quantum system.
In two and three dimensions, there is a similar formulation of stationary scattering where the scattering properties of the scatterer are extracted from the evolution operator.
We obtain explicit formulas for low-frequency scattering amplitude, examine their effectiveness in the study of a class of exactly solvable scattering problems, and outline their application in devising a low-frequency cloaking scheme.
- Score: 0.0
- License:
- Abstract: The transfer matrix of scattering theory in one dimension can be expressed in terms of the time-evolution operator for an effective non-unitary quantum system. In particular, it admits a Dyson series expansion which turns out to facilitate the construction of the low-frequency series expansion of the scattering data. In two and three dimensions, there is a similar formulation of stationary scattering where the scattering properties of the scatterer are extracted from the evolution operator for a corresponding effective quantum system. We explore the utility of this approach to scattering theory in the study of the scattering of low-frequency time-harmonic scalar waves, $e^{-i\omega t}\psi(\mathbf{r})$, with $\psi(\mathbf{r})$ satisfying the Helmholtz equation, $[\nabla^2+k^2\hat\varepsilon(\mathbf{r};k)]\psi(\mathbf{r})=0$, $\omega$ and $k$ being respectively the angular frequency and wavenumber of the incident wave, and $\hat\varepsilon(\mathbf{r};k)$ denoting the relative permittivity of the carrier medium which in general takes complex values. We obtain explicit formulas for low-frequency scattering amplitude, examine their effectiveness in the study of a class of exactly solvable scattering problems, and outline their application in devising a low-frequency cloaking scheme.
Related papers
- Exact dynamics of quantum dissipative $XX$ models: Wannier-Stark localization in the fragmented operator space [49.1574468325115]
We find an exceptional point at a critical dissipation strength that separates oscillating and non-oscillating decay.
We also describe a different type of dissipation that leads to a single decay mode in the whole operator subspace.
arXiv Detail & Related papers (2024-05-27T16:11:39Z) - Quantum tomography of helicity states for general scattering processes [55.2480439325792]
Quantum tomography has become an indispensable tool in order to compute the density matrix $rho$ of quantum systems in Physics.
We present the theoretical framework for reconstructing the helicity quantum initial state of a general scattering process.
arXiv Detail & Related papers (2023-10-16T21:23:42Z) - Third quantization of open quantum systems: new dissipative symmetries
and connections to phase-space and Keldysh field theory formulations [77.34726150561087]
We reformulate the technique of third quantization in a way that explicitly connects all three methods.
We first show that our formulation reveals a fundamental dissipative symmetry present in all quadratic bosonic or fermionic Lindbladians.
For bosons, we then show that the Wigner function and the characteristic function can be thought of as ''wavefunctions'' of the density matrix.
arXiv Detail & Related papers (2023-02-27T18:56:40Z) - Quantum chaos in a harmonic waveguide with scatterers [0.0]
A set of zero-range scatterers along its axis lifts the integrability of a harmonic waveguide.
Integrability-chaos transition can be explored as the model chaoticity increases with the number of scatterers.
The regime of complete quantum chaos and eigenstate thermalization can be approached with 32 scatterers.
arXiv Detail & Related papers (2023-01-15T10:27:10Z) - Dilute neutron star matter from neural-network quantum states [58.720142291102135]
Low-density neutron matter is characterized by the formation of Cooper pairs and the onset of superfluidity.
We model this density regime by capitalizing on the expressivity of the hidden-nucleon neural-network quantum states combined with variational Monte Carlo and reconfiguration techniques.
arXiv Detail & Related papers (2022-12-08T17:55:25Z) - Calculating non-linear response functions for multi-dimensional
electronic spectroscopy using dyadic non-Markovian quantum state diffusion [68.8204255655161]
We present a methodology for simulating multi-dimensional electronic spectra of molecular aggregates with coupling electronic excitation to a structured environment.
A crucial aspect of our approach is that we propagate the NMQSD equation in a doubled system Hilbert space but with the same noise.
arXiv Detail & Related papers (2022-07-06T15:30:38Z) - Multiple scattering model of the quantum random Lorentz gas [0.0]
A multiple scattering model of a quantum particle interacting with a random Lorentz gas of fixed point scatterers is established.
The fundamental properties of the model, such as the cross section and the scattering matrix, are calculated.
A distinct Airy diffraction peak is obtained for a large enough number of scatterers.
arXiv Detail & Related papers (2021-11-04T20:05:58Z) - Exceptional points and pseudo-Hermiticity in real potential scattering [0.0]
We study a class of scattering setups modeled by real potentials in two dimensions.
Our results reveal the relevance of the concepts of pseudo-Hermitian operator and exceptional point in the standard quantum mechanics of closed systems.
arXiv Detail & Related papers (2021-10-12T10:51:26Z) - Fano Resonances in Quantum Transport with Vibrations [50.591267188664666]
Quantum mechanical scattering continuum states coupled to a scatterer with a discrete spectrum gives rise to Fano resonances.
We consider scatterers that possess internal vibrational degrees of freedom in addition to discrete states.
arXiv Detail & Related papers (2021-08-07T12:13:59Z) - Low-frequency scattering defined by the Helmholtz equation in one
dimension [0.0]
The Helmholtz equation in one dimension describes the propagation of electromagnetic waves in effectively one-dimensional systems.
The fact that the potential term entering the latter is energy-dependent obstructs the application of the results on low-energy quantum scattering.
We use a recently developed dynamical formulation of stationary scattering to offer a comprehensive treatment of the low-frequency scattering of these waves for a general finite-range scatterer.
arXiv Detail & Related papers (2021-05-14T11:58:01Z) - Dynamical formulation of low-energy scattering in one dimension [0.0]
A transfer matrix $mathbfM$ of a short-range potential may be expressed in terms of the time-evolution operator for an effective two-level quantum system.
We explore the utility of this formulation in the study of the low-energy behavior of the scattering data.
arXiv Detail & Related papers (2021-02-11T15:55:34Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.