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تسجيل مستخدم جديدHigh sensitivity magnetic imaging using an array of spins in diamond
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We present a solid state magnetic field imaging technique using a two dimensional array of spins in diamond. The magnetic sensing spin array is made of nitrogen-vacancy (NV) centers created at shallow depths. Their optical response is used for measuring external magnetic fields in close proximity. Optically detected magnetic resonance (ODMR) is readout from a 60x60 $mu$m field of view in a multiplexed manner using a CCD camera. We experimentally demonstrate full two-dimensional vector imaging of the magnetic field produced by a pair of current carrying micro-wires. The presented widefield NV magnetometer offers in addition to its high magnetic sensitivity of 20 nT/$sqrt{Hz}$ and vector reconstruction, an unprecedented spatio-temporal resolution and functionality at room temperature.
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Quantum control of individual spins in condensed matter systems is an emerging field with wide-ranging applications in spintronics, quantum computation, and sensitive magnetometry. Recent experiments have demonstrated the ability to address and manip
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s which can be measured using Optically Detected Magnetic Resonance (ODMR). In this work, we exploit the ODMR signal of an ensemble of NV centers in order to quantitatively map the vectorial structure of a magnetic field produced by a sample close to the surface of a CVD diamond hosting a thin layer of NV centers. The reconstruction of the magnetic field is based on a maximum-likelihood technique which exploits the response of the four intrinsic orientations of the NV center inside the diamond lattice. The sensitivity associated to a 1 {mu}m^2 area of the doped layer, equivalent to a sensor consisting of approximately 10^4 NV centers, is of the order of 2 {mu}T/sqrt{Hz}. The spatial resolution of the imaging device is 400 nm, limited by the numerical aperture of the optical microscope which is used to collect the photoluminescence of the NV layer. The versatility of the sensor is illustrated by the accurate reconstruction of the magnetic field created by a DC current inside a copper wire deposited on the diamond sample.
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ditional peak and minimum according to pinned orbits at antidots and to propagating orbits in transport direction, respectively.
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