We present a laser-based atomic magnetometer that allows inferring the modulus of a magnetic field from the free Larmor precession of spin-oriented Cs vapour atoms. The detection of free spin precession (FSP) is not subject to systematic readout errors that occur in phase feedback-controlled magnetometers in which the spin precession is actively driven by an oscillating field or a modulation of...

Human body movement can be monitored through a wireless network composed of inertial sensors. This work presents the development of Wagyromag (Wireless Accelerometer, GYROscope and MAGnetometer), a wireless Inertial Measurement Unit (IMU) composed of a triaxial accelerometer, gyroscope and magnetometer. Communication is based on a 802.15.4 network. Furthermore, calibration, signal conditioning ...

We present a framework called Semantic Streams that allows users to pose declarative queries over semantic interpretations of sensor data. For example, instead of querying raw magnetometer data, the user queries whether vehicles are cars or trucks; the system decides which sensor data and which operations to use to infer the type of vehicle. The user can also place constraints on values such as...

A ferromagnetic metal consists of localized electrons and conduction coupled through strong exchange interaction. Together, these contribute to the magnetization system, while lead formation spin charge current. Femtosecond out equilibrium photoexcitation thin films generates a transient current at ultrafast timescales that have opened route probe magnetism offered by electrons. In presence nei...

Seafloor observatories have been the important way to observe the ocean, but applying the magnetometers to it still remain technical problems. This paper presents a smart cheaper magnetometer which was designed as the sensor node for a small seafloor network for geomagnetic observation. System design was described in modules at first. The calibration method of the whole system so as to alleviat...

We describe an alkali-metal magnetometer for detection of weak magnetic fields in the radio-frequency (rf) range. High sensitivity is achieved by tuning the Zeeman resonance of alkali atoms to the rf frequency and partially suppressing spin-exchange collisions in the alkali-metal vapor. We demonstrate magnetic field sensitivity of 2 fT/Hz(1/2) at a frequency of 99 kHz with a resonance width of ...

Scalar atomic magnetometers have many attractive features but their sensitivity has been relatively poor. We describe a Rb scalar gradiometer using two multipass optical cells. We use a pump-probe measurement scheme to suppress spin-exchange relaxation and two probe pulses to find the spin precession zero crossing times with a resolution of 1 psec. We realize a magnetic field sensitivity of 0.5...