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Related papers: Detection of low-conductivity objects using eddy c…

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Electrically conductive objects can be detected using the principle of electromagnetic induction where a primary oscillating magnetic field induces eddy currents in the object, which in turn produce a secondary magnetic field that can be…

Applied Physics · Physics 2022-12-06 L. M. Rushton , T. Pyragius , A. Meraki , L. Elson , K. Jensen

We use a radio-frequency $^{85}$Rb alkali-vapor cell magnetometer based on a paraffin-coated cell with long spin-coherence time and a small, low-inductance driving coil to create highly resolved conductivity maps of different objects. We…

Instrumentation and Detectors · Physics 2016-05-25 Arne Wickenbrock , Nathan Leefer , John W. Blanchard , Dmitry Budker

Eddy currents induced in electrically conductive objects can be used to locate metallic objects as well as to assess the properties of materials non-destructively without physical contact. This technique is useful for material…

Applied Physics · Physics 2023-01-19 Lucy Elson , Adil Meraki , Lucas M. Rushton , Tadas Pyragius , Kasper Jensen

Being able to characterise objects at low frequencies, but above the limiting frequency of the eddy current approximation of the Maxwell system, is important for improving current metal detection technologies. Importantly, the upper…

Analysis of PDEs · Mathematics 2022-09-28 P. D. Ledger , W. R. B. Lionheart

Sensitive magnetometers have been applied in a wide range of research fields, including geophysical exploration, bio-magnetic field detection, ultralow-field nuclear magnetic resonance, etc. Commonly, magnetometers are directly placed at…

We demonstrate microwave-free eddy-current imaging using nitrogen-vacancy centers in diamond. By detecting the eddy-current induced magnetic field of conductive samples, we can distinguish between different materials and shapes and identify…

In this paper we introduce an efficient algorithm for identifying conductive objects using induction data derived from eddy currents. Our method consists of first extracting geometric features from the induction data and then matching them…

Analysis of PDEs · Mathematics 2014-07-11 Habib Ammari , Junqing Chen , Zhiming Chen , Darko Volkov , Han Wang

The goal of this paper is to contribute to the field of nondestructive testing by eddy currents. We provide a mathematical analysis and a numerical framework for simulating the imaging of arbitrarily shaped small volume conductive…

Analysis of PDEs · Mathematics 2013-04-01 Habib Ammari , Junqing Chen , Zhiming Chen , Josselin Garnier , Darko Volkov

The inductive response of an object to an oscillating magnetic field reveals information about its electrical conductivity and magnetic permeability. Here we introduce a technique that uses measurements of the angular, frequency and spatial…

Applied Physics · Physics 2021-11-24 R. Gartman , W. Chalupczak

Electromagnetic induction imaging with atomic magnetometers has disclosed unprecedented domains for imaging, from security screening to material characterization. However, applications to low-conductivity specimens -- most notably for…

Atomic Physics · Physics 2019-09-02 Luca Marmugi , Cameron Deans , Ferruccio Renzoni

Optical magnetometers are currently able to achieve magnetometric sensitivities below 1 fT/Hz^1/2. Although such sensitivities are typically obtained for ultra-low-field measurements, a group of optical magnetometers allows the detection of…

Atomic Physics · Physics 2015-06-03 Przemyslaw Wlodarczyk , Szymon Pustelny , Jerzy Zachorowski , Marcin Lipinski

We report on the use of radio-frequency optical atomic magnetometers for magnetic induction tomography measurements. We demonstrate the imaging of dummy targets of varying conductivities placed in the proximity of the sensor, in an…

Atomic Physics · Physics 2016-05-04 Cameron Deans , Luca Marmugi , Sarah Hussain , Ferruccio Renzoni

We describe our research programme on the use of atomic magnetometers to detect conductive objects via electromagnetic induction. The extreme sensitivity of atomic magnetometers at low frequencies, up to seven orders of magnitude higher…

Atomic Physics · Physics 2016-05-09 Sarah Hussain , Luca Marmugi , Cameron Deans , Ferruccio Renzoni

We present a method of optical magnetometry with parts-per-billion resolution that is able to detect biomagnetic signals generated from the human brain and heart in Earth's ambient environment. Our magnetically silent sensors measure the…

Medical Physics · Physics 2020-07-29 M. E. Limes , E. L. Foley , T. W. Kornack , S. Caliga , S. McBride , A. Braun , W. Lee , V. G. Lucivero , M. V. Romalis

A method of electronic conductivity measurement is presented. It combines two well known methods of electrochemistry: cyclic voltammetry and chronoamperometry. This DC technique uses the Hebb/Wagner approach to block ionic conduction when…

Systems and Control · Electrical Eng. & Systems 2024-10-01 Veyis Gunes , Jean-Yves Botquelen , Odile Bohnke

We present a current monitoring system based on optical magnetometry, which is able to discriminate true current variations from environmental effects at room temperature. The system consists of a dedicated thermally stable magnetic field…

Instrumentation and Detectors · Physics 2021-07-14 Peter A. Koss , Reza Tavakoli Dinani , Luc Bienstman , Georg Bison , Nathal Severijns

Quantum measurement principle is employed to detect water quality and presence of nano-colloids. The setup uses spatially low coherent light source, for which the outcome of measurement is dependent on the presence of a reflecting surface…

Optics · Physics 2016-01-05 Sufi O Raja , Anjan K Dasgupta

Quantum sensors provide unprecedented magnetic field detection sensitivities, enabling these to extend the common magnetometry range of applications and environments of operation. In this framework, many applications also require high…

Applied Physics · Physics 2023-05-02 Marc Jofre , Jordi Romeu , Luis Jofre-Roca

We demonstrate an all-optical magnetometer capable of measuring the magnitude and direction of a magnetic field using nonlinear magneto-optical rotation in a cesium vapor. Vector capability is added by effective modulation of the field…

Atomic Physics · Physics 2015-06-19 B. Patton , E. Zhivun , D. C. Hovde , D. Budker

We investigate detection of magnetic data using magnetooptical indicators with in-plane magnetization. A simple model for the magnetooptical detection system is presented. We find that the signal to noise ratio changes strongly with the bit…

Materials Science · Physics 2007-05-23 L. E. Helseth , E. I. Il'yashenko , M. Baziljevich , T. H. Johansen
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