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Related papers: Factorization method versus migration imaging in a…

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We propose and demonstrate two methods for modal decomposition in multi-mode fibres. Linearly polarized modes propagating in a slightly multi-mode fibre are easily retrieved from intensity measurements at the fibre output surface. The first…

Photo-acoustic tomography is a coupled-physics (hybrid) medical imaging modality that aims to reconstruct optical parameters in biological tissues from ultrasound measurements. As propagating light gets partially absorbed, the resulting…

Analysis of PDEs · Mathematics 2020-01-08 Guillaume Bal , Adrian Kirkeby

A sampling method by using scattering amplitude is proposed for shape and location reconstruction in inverse acoustic scattering problems. Only matrix multiplication is involved in the computation, thus the novel sampling method is very…

Numerical Analysis · Mathematics 2017-09-13 Xiaodong Liu

Matter-wave interferometry with solids is highly susceptible to minute fluctuations of environmental fields, including gravitational effects from distant sources. Hence, experiments require a degree of shielding that is extraordinarily…

Quantum Physics · Physics 2022-08-23 Julen S. Pedernales , Martin B. Plenio

The use of the Factorization method for Electrical Impedance Tomography has been proved to be very promising for applications in the case where one wants to find inhomogeneous inclusions in a known background. In many situations, the…

Analysis of PDEs · Mathematics 2015-06-18 Nicolas Chaulet , Simon Arridge , Timo Betcke , David Holder

In this paper we consider the inverse acoustic scattering (in \mathbb{R}^3) or electromagnetic scattering (in \mathbb{R}^2, for the scalar TE-polarization case) problem of reconstructing possibly multiple defective penetrable regions in a…

Analysis of PDEs · Mathematics 2015-10-08 Fioralba Cakoni , Isaac Harris

Long-distance transmission of energy by waves is a key mechanism for many natural processes. It becomes possible when the inhomogeneous medium is arranged in such a manner that it enables a specific type of waves to propagate with virtually…

Fluid Dynamics · Physics 2024-11-18 Semyon Churilov

This paper considers wave-based imaging through a heterogeneous (random) scattering medium. The goal is to estimate the support of the reflectivity function of a remote scene from measurements of the backscattered wave field. The proposed…

Image and Video Processing · Electrical Eng. & Systems 2021-05-27 Liliana Borcea , Josselin Garnier

With the recent success of representation learning methods, which includes deep learning as a special case, there has been considerable interest in developing representation learning techniques that can incorporate known physical…

Machine Learning · Computer Science 2021-09-10 Harsha Vardhan Tetali , Joel B. Harley , Benjamin D. Haeffele

Sound speed heterogeneities can create aberrations in B-mode ultrasound images by inducing tissue-dependent delays and diffractive effects that conventional beamforming does not incorporate. By using the Fourier split-step method to…

Medical Physics · Physics 2026-05-01 Rehman Ali , Trevor M. Mitcham , Marvin M. Doyley , Nebojsa Duric , Jeremy J. Dahl

We introduce a versatile numerical method for modeling light diffraction in periodically patterned photonic structures containing quadratically nonlinear non-centrosymmetric optical materials. Our approach extends the generalized source…

Optics · Physics 2015-06-23 Martin Weismann , Dominic F. G. Gallagher , Nicolae C. Panoiu

Consider the inverse problem of scattering of time-harmonic acoustic waves by an inhomogeneous medium with complex refractive index. We show that an approximate factorization method can be applied to reconstruct the support of the complex…

Numerical Analysis · Mathematics 2019-03-27 Fenglong Qu , Haiwen Zhang

Wavefront shaping can tailor multipath interference to control multiple scattering of waves in complex optical systems. However, full-wave simulations that capture multiple scattering are computationally demanding given the large system…

Optics · Physics 2024-06-14 Ho-Chun Lin , Zeyu Wang , Chia Wei Hsu

We present a novel frequency-filtering method for measuring and calculating frequency-filtered photon-correlations. This novel method is a cavity-based system we call the multi-mode array filter, which consists of an array of tunable…

Quantum Physics · Physics 2024-08-20 Jacob Ngaha , Scott Parkins , Howard J. Carmichael

Wave propagation through waveguides, quantum wires or films with a modest amount of disorder is in the semi-ballistic regime when in the transversal direction(s) almost no scattering occurs, while in the long direction(s) there is so much…

Condensed Matter · Physics 2009-10-28 A. Mosk , Th. M. Nieuwenhuizen , C. Barnes

The first part of this paper is concerned with the uniqueness to inverse time-harmonic elastic scattering from bounded rigid obstacles in two dimensions. It is proved that a connected polygonal obstacle can be uniquely identified by the…

Analysis of PDEs · Mathematics 2019-09-04 Johannes Elschner , Guanghui Hu

The characterisation of loss in optical waveguides is essential in understanding the performance of these devices and their limitations. Whilst interferometric-based methods generally provide the best results for low-loss waveguides, they…

This paper is concerned with the inverse acoustic scattering problems by an obstacle or a cavity with a sound-soft or a sound-hard boundary. A direct imaging method relying on the boundary conditions is proposed for reconstructing the shape…

Numerical Analysis · Mathematics 2022-02-21 Deyue Zhang , Yue Wu , Yinglin Wang , Yukun Guo

We report on the fabrication and characterization of composite multimode waveguide structures that consist of a stack of single-mode waveguides fabricated by ultrafast laser inscription. We explore 2 types of composite structures; those…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Nemanja Jovanovic , Izabela Spaleniak , Simon Gross , Michael Ireland , Jon S. Lawrence , Christopher Miese , Alexander Fuerbach , Michael J. Withford

Analyzing the internal loss characteristics and multimodedness of (integrated) optical devices can prove difficult. One technique to recover this information is to Fourier transform the transmission spectrum of optical components. This…