Our work relates to the use of metamaterials engineered to realize a metasurface approaching the exotic properties of an ideal object not observed in nature, a "magnetic mirror." Previous realizations were based on resonant structures that implied narrow bandwidths and large losses. The working principle of our device is ideally frequency-independent, it does not involve resonances and it does ...

We have discovered a security vulnerability in the Samsung Pay app. The magnetic secure transmission in Samsung Pay emits too many magnetic signals that are excessively strong. Thus, we built a low-cost receiver to eavesdrop on the emitted magnetic signals. Using this receiver, we successfully eavesdropped the one-time token for a payment made on the Samsung Pay app around 0.6m ∼ 2.0m from wher...

Optically pumped magnetometers (OPMs) based on lasers and alkali-metal vapor cells are currently the most sensitive non-cryogenic magnetic field sensors. Many applications in neuroscience and other fields require high-resolution, high-sensitivity magnetic microscopic measurements. In order to meet this demand we combined a cm-size spin-exchange relaxation-free (SERF) OPM and flux guides (FGs) t...

Nucleic acids serve as biomarkers of disease and it is highly desirable to develop approaches to extract small number of such genomic extracts from human bodily fluids. Magnetic particles-based nucleic acid extraction is widely used for concentration of small amount of samples and is followed by DNA amplification in specific assays. However, approaches to integrate such magnetic particles based...

Electromagnetic field probes inevitably change the original field distribution to some extent when they are positioned close to a device. That change affects measurement accuracy and the device operation. We have developed optical magnetic field probes, which comprise a loop antenna element and an electro-optic crystal, to perform magnetic nearfield measurement with high accuracy in the GHz fre...

We show how the static magnetic field of a finite source can be transferred and routed to arbitrary long distances. This is achieved by using transformation optics, which results in a device made of a material with a highly anisotropic magnetic permeability. We show that a simplified version of the device, made by a superconducting-ferromagnet hybrid, also leads to an excellent transfer of the ...