Abstract: In a general aspect, a vapor cell includes a body defined by a stack of layers that includes electrically conductive layers and electrically insulating layers. The stack of layers are bonded to each other and have first and second end layers at respective opposite ends of the body. The stack of layers also has intermediate layers between the first and second end layers that define an internal cavity of the body. The internal cavity extends through the body between the first and second end layers and includes a vapor or a source of the vapor disposed therein. Adjacent electrically conductive layers are separated by at least one electrically insulating layer. Moreover, each electrically conductive layer defines an electrode of the vapor cell and includes a contact surface on an exterior side of the body. The contact surface defines an electrical contact of the electrode.

Abstract: In a general aspect, radio frequency (RF) electromagnetic radiation can be detected using vapor cell sensors. In some aspects, a system includes a laser system that is configured to generate laser signals that comprise first and second laser signals. The system also includes an optical comb generator and a vapor cell sensor. The optical comb generator is configured to generate a comb spectrum based on the first laser signal. The comb spectrum includes comb lines at respective comb frequencies. The vapor cell sensor contains a vapor and is configured to generate an optical spectrum based on interactions of the vapor with the comb spectrum and the second laser signal. The system also includes an optical detector that is configured to detect the property of the optical spectrum at one or more of the comb frequencies.

Abstract: In a general aspect, a system for sensing pulses of radio frequency (RF) fields includes a laser system and a vapor cell sensor. The laser system is configured to generate beams of light that include a probe beam of light. The vapor cell sensor has a vapor therein and is configured to allow the beams of light to pass through the vapor. The system also includes an optical detector configured to generate a detector signal based on the probe beam of light. The system includes a signal processing system configured to perform operations that include receiving the detector signal from the optical detector over a time period. The operations also include generating a digital signal based on the detector signal and applying a matched filter to the digital signal to generate a filtered signal. The filtered signal is processed to determine properties of an RF field experienced by the vapor.

Abstract: In a general aspect, a method includes interacting a beam of light with a vapor in a vapor cell. The vapor cell includes a body defined by a stack of layers that includes electrically conductive layers and electrically insulating layers. The stack of layers are bonded to each other and have first and second end layers at respective opposite ends of the body. The stack of layers also has intermediate layers between the first and second end layers that define an internal cavity of the body. A vapor is disposed in the internal cavity. The method includes applying respective voltages to one or more electrodes to alter an electric field in the internal cavity. The method also includes measuring one or both of an ion signal based on charged particles in the vapor and an optical property of the beam of light after interacting with the vapor.

Abstract: In a general aspect, radio frequency (RF) electromagnetic radiation can be detected using vapor cell sensors. In some aspects, a system includes a laser system that is configured to generate laser signals that comprise first and second laser signals. The system also includes an optical comb generator and a vapor cell sensor. The optical comb generator is configured to generate a comb spectrum based on the first laser signal. The comb spectrum includes comb lines at respective comb frequencies. The vapor cell sensor contains a vapor and is configured to generate an optical spectrum based on interactions of the vapor with the comb spectrum and the second laser signal. The system also includes an optical detector that is configured to detect the property of the optical spectrum at one or more of the comb frequencies.

Abstract: In a general aspect, a system for sensing pulses of radio frequency (RF) fields includes a laser system and a vapor cell sensor. The laser system is configured to generate beams of light that include a probe beam of light. The vapor cell sensor has a vapor therein and is configured to allow the beams of light to pass through the vapor. The system also includes an optical detector configured to generate a detector signal based on the probe beam of light. The system includes a signal processing system configured to perform operations that include receiving the detector signal from the optical detector over a time period. The operations also include generating a digital signal based on the detector signal and applying a matched filter to the digital signal to generate a filtered signal. The filtered signal is processed to determine properties of an RF field experienced by the vapor.

Abstract: In a general aspect, a radar system includes a vapor cell sensor system and a radio frequency (RF) optic. The vapor cell sensor system includes a vapor cell sensor, and the RF optic is configured to direct an RF field onto the vapor cell sensor. The RF field includes one or more RF pulses that define a radar signal. The radar system also includes a signal processing system configured to perform operations that include generating a digital signal based on a signal from the vapor cell sensor system. The digital signal represents a measured response of the vapor to the RF field over a time period. The operations also include applying a matched filter to the digital signal to generate a filtered signal and processing the filtered signal to determine properties of the RF field sensed by the vapor cell sensor over the time period.

Abstract: In a general aspect, a radar system includes a vapor cell sensor system and a radio frequency (RF) optic. The vapor cell sensor system includes a vapor cell sensor, and the RF optic is configured to direct an RF field onto the vapor cell sensor. The RF field includes one or more RF pulses that define a radar signal. The radar system also includes a signal processing system configured to perform operations that include generating a digital signal based on a signal from the vapor cell sensor system. The digital signal represents a measured response of the vapor to the RF field over a time period. The operations also include applying a matched filter to the digital signal to generate a filtered signal and processing the filtered signal to determine properties of the RF field sensed by the vapor cell sensor over the time period.

Abstract: A method and system for independently sequestering liquid calcium chloride and pure solid sodium chloride from a solid salt waste mixture including calcium chloride, sodium chloride and impurities. In practice, the method includes a calcium chloride sequestration step, wherein the waste mixture is combined with water, maintaining the calcium chloride within the mixture at least 30% w/w, and the resulting liquid calcium chloride is decanted from such mixture. The remaining salt particulates may be depured by a depuration process, which may include the recycling of salt brine through the depuration process. Particulate impurities in the solid salt waste mixture may also be removed in practice of the methods of the disclosed technology, by means of one or more clarifiers.

Abstract: One embodiment of a method of water treatment comprising straining fractionated water to remove particles larger than one micron in diameter, decanting the strained fractionated water to remove surfactants and oil, evaporating the decanted water to provide concentrated brine and water vapor, and condensing the water vapor.

Abstract: Described herein are devices and techniques for automating vehicle mounted spreading systems such as deicing systems for winter road maintenance vehicles and/or agricultural spreading systems by use of an electronic control system configured to operate a distribution element drive system.

Abstract: One embodiment of a method of water treatment comprising straining fractionated water to remove particles larger than one micron in diameter, decanting the strained fractionated water to remove surfactants and oil, evaporating the decanted water to provide concentrated brine and water vapor, and condensing the water vapor.