Abstract: Disclosed is a method of generating atomic spin orientation in an atomic ensemble. The method includes providing a steady magnetic field (5) to the atomic ensemble to cause a Zeeman splitting within first and second manifolds of the ground state of the atomic energy levels of the atomic ensemble. The method includes pumping the atomic ensemble with an electromagnetic optical radiation beam, the beam being detuned from a transition involving the first manifold such that a majority of the atomic population of the first manifold in the atomic ensemble is transferred from the first manifold into a magnetic Zeeman sublevel of the second manifold. A system for generating an atomic spin orientation in a 15 atomic ensemble is also disclosed.

Abstract: Methods and apparatuses of identifying a type of material or material combination in a measurement location by Magnetic Induction Tomography (MIT) is disclosed. The methods can comprise providing a primary magnetic field primarily in a first direction into the measurement location; measuring an orthogonal component of a secondary magnetic field; classifying the orthogonal component of the secondary magnetic field with reference to a material or material combination type and thereby identifying a type of material or material combination in the measurement location. The orthogonal component of the secondary magnetic field is in a direction substantially orthogonal to the first direction.

Abstract: Disclosed herein is a method of detecting a material response. The method includes providing an oscillating primary magnetic field to cause as ample to produce a secondary magnetic field. The method also includes reducing the effect on an atomic magnetometer of components of the primary and secondary magnetic fields in a direction substantially orthogonal to a surface of the sample. The method also includes detecting the secondary magnetic field with the atomic magnetometer to detect the material response.

Abstract: An atomic magnetometer system is disclosed that includes a variable magnetic field source (14) configured to provide an oscillating primary magnetic field to cause a sample (16) to produce a secondary magnetic field. The atomic magnetometer system also includes an atomic magnetometer for detecting the secondary magnetic field. The atomic magnetometer includes an atomic specimen, a pump and probe subsystem configured to pump the atomic specimen to create a polarisation and to probe atomic coherence precession within the atomic specimen with a probe beam, a detector configured to detect the probe beam to produce a detection signal. The system is configured to drive the variable magnetic field source (14) in dependence on the detection signal with a frequency tuned to rf resonance. A method of operating an atomic magnetometer is also disclosed.

Abstract: Disclosed herein is a method of detecting a material response. The method includes providing an oscillating primary magnetic field to cause a sample to produce a secondary magnetic field. The method also includes reducing the effect on an atomic magnetometer of components of the primary and secondary magnetic fields in a direction substantially orthogonal to a surface of the sample. The method also includes detecting the secondary magnetic field with the atomic magnetometer to detect the material response.