Method and Apparatus for Implementing EIT Magnetometry
AssigneeEntanglement Technologies, LLC
InventorAri K. Tuchman
Life of this patent
Estimating the term…
Abstract
A magnetometer is provided comprising an atomic vapor in an enclosure, a source of light for preparing the vapor into a state exhibiting electromagnetically induced transparency, a first laser beam passing through the atomic vapor, a phase detector for detecting changes in phase of the first laser beam, and a controller which controls the light source and laser beam and receives the information detected by the phase detector in order to compute from those changes in phase a magnetic field strength in the presence of a selected background magnetic field of at least 0.001 T. Operation in the presence of a background field helps make this magnetometer suitable for diagnostic imaging applications.
Claims27
A magnetometer comprising an atomic vapor in an enclosure, a source of light for preparing the vapor into a state exhibiting electromagnetically induced transparency, a first laser beam passing through the atomic vapor, a phase detector for detecting changes in phase of the first laser beam, and a controller which controls the light source and first laser beam and receives the information detected by the phase detector in order to compute from those changes in phase a magnetic field strength in the presence of a selected background measurement magnetic field of at least 0.001 T, wherein the source of light is capable of producing light which places the vapor in a state exhibiting electromagnetically induced transparency.
A gradiometer comprising two magnetometers in proximity to each other and a controller, wherein each magnetometer comprises an atomic vapor in an enclosure and an apparatus generating a laser beam passing through the atomic vapor, wherein the two magnetometers have opposite effects on the phases of their respective laser beams in the presence of a magnetic field.
A method of diagnostic imaging comprising (a) exposing a subject to a pulsed magnetic field of at least about 0.25 T, (b) exposing a subject to a magnetic field of at least about 0.001 T which is substantially spatially homogeneous in a region of interest of the subject, (c) exposing the subject to a radiofrequency pulse which causes nuclei of atoms within the subject to experience spin precession, (d) subjecting the subject to an additional magnetic field, (e) providing a cell containing an atomic vapor, (f) preparing the atomic vapor in a state that exhibits electromagnetically induced transparency, (g) traversing the atomic vapor with a laser beam, (h) detecting a characteristic of the laser beam, (i) using as an input the detected characteristic and the characteristics of the additional magnetic field, estimating a function of the spin precession caused by the radiofrequency pulse, and (j) using the estimated function of the spin precession to produce an image of the region of interest.
A nuclear magnetic resonance gyroscope, comprising an atomic vapor in an enclosure, a magnet for generating a magnetic field in an area surrounding the enclosure containing the atomic vapor, a source of light for preparing the vapor into a state exhibiting electromagnetically induced transparency, a first laser beam passing through the atomic vapor, a phase detector for detecting changes in phase of the first laser beam, and a controller which controls the light source and first laser beam and receives the information detected by the phase detector in order to compute from those changes in phase a magnetic field strength and thereby compute spectroscopic changes due to rotation.
Dependencies are inferred from the claim text.