A stable single-carrier optical spring, comprising a pair of dielectric mirrors, each having a dielectric coating, and positioned to form a standing wave from an incident optic field. The dielectric coating has a plurality of layers, where at least the first layer is sized to be an odd multiple of half a wavelength of the laser beam, to feature an opposite-sign photo-thermal effect due to the detailed interaction of the optical field with the coating. This results in an opposite-sign photo-thermal effect at the optical spring frequency. The dampening effect is large enough to stabilize the radiation pressure based optical spring, resulting in a statically and dynamically stable optical spring. As a result this coating allows stable locking of a cavity with a single laser frequency using radiation pressure feedback.

The method of monitoring carbon dioxide leakage in carbon capture and storage reservoirs estimates porosity and water saturation in a porous medium, such as brine-saturated shale, as is common in carbon capture and storage reservoirs, based upon measured electrical conductivity and seismic P-wave velocity. The estimated porosity and water saturation may be used for monitoring carbon dioxide leakage from a carbon dioxide reservoir to the overlying cap rock of the region. Measured electrical conductivity and seismic P-wave velocity data are used by the present method to estimate the porosity and water saturation in the cap rock. If a decrease in water saturation in the cap rock is found, this indicates that carbon dioxide may be leaking up from the carbon dioxide reservoir. An alert signal is then generated to indicate that there may be a carbon dioxide leak.

The present invention is a method for simultaneously measuring magnetic/magnetic gradient and gravitational fields using atom interferometers includes the steps of releasing laser cooled atoms from a trap, further cooling the released atoms, launching the atoms vertically, preparing the atoms into well-known atomic states, measuring gravity from the atoms as the atoms travel upward, and measuring the magnetic field of the atoms the begin to fall.

A rotary switch state detection device includes a magnetic field generating unit, a gravity sensing unit, a magnetic force sensing unit and a processing unit. The magnetic field generating unit generates a magnetic field. The magnetic force sensing unit and the gravity sensing unit are disposed at a rotary switch to detect a gravity value and a magnetic force value of the magnetic field and generate a gravity strength signal and magnetic field strength signal, respectively. The processing unit is connected to the gravity sensing unit and the magnetic force sensing unit to calculate a gravity value variation and a magnetic force value variation and thereby precisely locate a rotation head of the rotary switch upon completion of rotation thereof.

A rotary switch state detection device includes a magnetic field generating unit, a gravity sensing unit, a magnetic force sensing unit and a processing unit. The magnetic field generating unit generates a magnetic field. The magnetic force sensing unit and the gravity sensing unit are disposed at a rotary switch to detect a gravity value and a magnetic force value of the magnetic field and generate a gravity strength signal and magnetic field strength signal, respectively. The processing unit is connected to the gravity sensing unit and the magnetic force sensing unit to calculate a gravity value variation and a magnetic force value variation and thereby precisely locate a rotation head of the rotary switch upon completion of rotation thereof.

A system method and computer-readable medium for correcting measurements obtained by a down hole tool for residual measurement errors is disclosed. A down hole tool having at least two directional field sensors is disposed in a borehole. The at least two directional sensors are substantially orthogonal to each other and to a longitudinal axis of the down hole tool. Measurements are obtained from the at least two directional sensors during rotation of the tool by at least 360 degrees around the longitudinal axis of the tool. Residual measurement errors are determined for the obtained measurements, and a quality level of the determined residual measurement errors selected. The determined residual measurement errors are applied to the obtained measurements when the determined residual measurement errors are consistent with the selected quality level. In various embodiments, the residual measurement errors are reduced from a first value that does not match the selected quality level to a second value that are consistent with the selected quality level.

A system method and computer-readable medium for correcting measurements obtained by a down hole tool for residual measurement errors is disclosed. A down hole tool having at least two directional field sensors is disposed in a borehole. The at least two directional sensors are substantially orthogonal to each other and to a longitudinal axis of the down hole tool. Measurements are obtained from the at least two directional sensors during rotation of the tool by at least 360 degrees around the longitudinal axis of the tool. Residual measurement errors are determined for the obtained measurements, and a quality level of the determined residual measurement errors selected. The determined residual measurement errors are applied to the obtained measurements when the determined residual measurement errors are consistent with the selected quality level. In various embodiments, the residual measurement errors are reduced from a first value that does not match the selected quality level to a second value that are consistent with the selected quality level.

An atomic interferometric accelerometer comprises a laser that emits a pulsed beam at a first frequency, an electro-optic modulator that receives the beam, and a vacuum cell in communication with the electro-optic modulator. The electro-optic modulator outputs a first optical signal corresponding to the beam at the first frequency and a second optical signal having a second frequency different from the first frequency. The vacuum cell has a chamber for laser cooled atoms. The vacuum cell receives the optical signals such that they propagate in a direction that passes through the atoms. A piezo mirror retro-reflects the optical signals back through the vacuum cell in a counter-propagating direction. The piezo mirror is driven with substantially constant velocity during a beam pulse, thereby imparting a Doppler shift to the retro-reflected optical signals to create two non-symmetric counter-propagating lightwave pairs. One of the lightwave pairs supports interferometry while the other is non-resonant.

A directional filter for processing full-tensor gradiometer data is described. The filter processes input data using a method comprising receiving geophysical data collected based on characteristics of geographic features in an environment, and applying a directional filter to the received geophysical data in a first instance so as to provide first filtered data. A filtering direction of the directional filter is determined based on properties in the received geophysical data. The method also includes updating the filtering direction based on properties in the first filtered data, applying the directional filter to the received geophysical data in a subsequent instance using the updated filtering direction so as to provide subsequent filtered data, and based on the updated filtering direction having a subsequent update less than a threshold, outputting directionally filtered data. The subsequent update is determined due to properties in the subsequent filtered data output from the subsequent instance.

A directional filter for processing full-tensor gradiometer data is described. The filter processes input data using a method comprising receiving geophysical data collected based on characteristics of geographic features in an environment, and applying a directional filter to the received geophysical data in a first instance so as to provide first filtered data. A filtering direction of the directional filter is determined based on properties in the received geophysical data. The method also includes updating the filtering direction based on properties in the first filtered data, applying the directional filter to the received geophysical data in a subsequent instance using the updated filtering direction so as to provide subsequent filtered data, and based on the updated filtering direction having a subsequent update less than a threshold, outputting directionally filtered data. The subsequent update is determined due to properties in the subsequent filtered data output from the subsequent instance.