0000000000798272
AUTHOR
Nazanin Mosavian
showing 5 related works from this author
Diamond magnetometer enhanced by ferrite flux concentrators
2020
Magnetometers based on nitrogen-vacancy (NV) centers in diamond are promising room-temperature, solid-state sensors. However, their reported sensitivity to magnetic fields at low frequencies (<1 kHz) is presently >10 pT s^{1/2}, precluding potential applications in medical imaging, geoscience, and navigation. Here we show that high-permeability magnetic flux concentrators, which collect magnetic flux from a larger area and concentrate it into the diamond sensor, can be used to improve the sensitivity of diamond magnetometers. By inserting an NV-doped diamond membrane between two ferrite cones in a bowtie configuration, we realize a ~250-fold increase of the magnetic field amplitude wi…
Diamond Magnetic Microscopy of Malarial Hemozoin Nanocrystals.
2019
Magnetic microscopy of malarial hemozoin nanocrystals was performed using optically detected magnetic resonance imaging of near-surface diamond nitrogen-vacancy centers. Hemozoin crystals were extracted from $Plasmodium$-$falciparum$-infected human blood cells and studied alongside synthetic hemozoin crystals. The stray magnetic fields produced by individual crystals were imaged at room temperature as a function of applied field up to 350 mT. More than 100 nanocrystals were analyzed, revealing the distribution of their magnetic properties. Most crystals ($96\%$) exhibit a linear dependence of stray field magnitude on applied field, confirming hemozoin's paramagnetic nature. A volume magneti…
Two-dimensional nuclear magnetic resonance spectroscopy with a microfluidic diamond quantum sensor
2019
Quantum sensors based on nitrogen-vacancy centers in diamond have emerged as a promising detection modality for nuclear magnetic resonance (NMR) spectroscopy owing to their micron-scale detection volume and non-inductive based detection. A remaining challenge is to realize sufficiently high spectral resolution and concentration sensitivity for multidimensional NMR analysis of picoliter sample volumes. Here, we address this challenge by spatially separating the polarization and detection phases of the experiment in a microfluidic platform. We realize a spectral resolution of 0.65 +/- 0.05 Hz, an order-of-magnitude improvement over previous diamond NMR studies. We use the platform to perform …
Solution nuclear magnetic resonance spectroscopy on a nanostructured diamond chip
2017
We demonstrate nuclear magnetic resonance (NMR) spectroscopy of picoliter-volume solutions with a nanostructured diamond chip. Using optical interferometric lithography, diamond surfaces were nanostructured with dense, high-aspect-ratio nanogratings, enhancing the surface area by more than a factor of 15 over mm^2 regions of the chip. The nanograting sidewalls were doped with nitrogen-vacancy (NV) centers so that more than 10 million NV centers in a (25 micrometer)^2 laser spot are located close enough to the diamond surface (5 nm) to detect the NMR spectrum of 1 pL of fluid lying within adjacent nanograting grooves. The platform was used to perform 1H and 19F NMR spectroscopy at room tempe…
Nuclear quadrupole resonance spectroscopy with a femtotesla diamond magnetometer
2023
Sensitive Radio-Frequency (RF) magnetometers that can detect oscillating magnetic fields at the femtotesla level are needed for demanding applications such as Nuclear Quadrupole Resonance (NQR) spectroscopy. RF magnetometers based on Nitrogen-Vacancy (NV) centers in diamond have been predicted to offer femtotesla sensitivity, but published experiments have largely been limited to the picotesla level. Here, we demonstrate a femtotesla RF magnetometer based on an NV-doped diamond membrane inserted between two ferrite flux concentrators. The device operates in bias magnetic fields of 2-10 microtesla and provides a ~300-fold amplitude enhancement within the diamond for RF magnetic fields in the…