Abstract: An apparatus for generating vertically separated atom clouds. The apparatus comprises an optical system comprising an arrangement of lenses and optics. The optical system is configured to trap and cool atoms to form a cold atom cloud; select the hyperfine level of the atoms; trap atoms of the cold atom cloud in a standing wave optical lattice; and vertically split the cold atom cloud into a high cold atom cloud and a low cold atom cloud. The splitting comprises splitting the cold atom cloud into two clouds by launching atoms of the cold atom cloud in opposite directions to form a high cold atom cloud and a low cold atom cloud, and catching the low cold atom cloud up to reach the same velocity as the high cold atom cloud.

Abstract: A single arm laser system comprising a first in-phase quadrature modulator, IQM. The first IQM is configured to receive a single frequency fibred laser beam from a frequency locked laser seed, generate a first single side-band frequency based on a carrier frequency of the single frequency fibred laser beam and suppress the carrier frequency, and output a first fibre laser beam having a single side-band suppressed carrier frequency. The single arm laser system also comprises a second IQM in line with the first IQM. The second IQM is configured to receive the first fibre laser beam from the first IQM, generate a second single side-band frequency based on the first single side-band frequency and maintain the first single side-band frequency as the carrier frequency, and output a second fibre laser beam having the first and second single side band frequencies.

Abstract: The application discloses an atom interferometer comprising an optical cavity and method of operation thereof. The atom interferometer includes a vacuum chamber, an optical cavity, a source for providing a cloud of atoms in the optical cavity in use, and one or more light sources. The one or more light sources are for generating, in the cavity, in use a first light beam having a first polarisation and at a first frequency for a two-photon interaction in the atoms; and a counterpropagating second light beam having a second polarisation orthogonal to the first polarisation and at a second frequency for the two-photon interaction in the atoms.

Abstract: An optical frequency manipulation using an optical subsystem configured to provide a modulated laser beam for interaction with an atomic sample. The optical system may include: an optical subsystem for producing a light beam, the optical subsystem having a laser source and an IQ modulator, wherein the IQ modulator is operable to modulate light from the laser source at a carrier frequency to produce modulated light having a single sideband at a sideband frequency; and a chamber for containing an atomic sample, wherein the optical subsystem is arranged to direct the light beam towards the chamber to interact with an atomic sample contained therein.

Abstract: The disclosure relates to a gravity gradiometer including a pair of magneto-optical traps for measuring a gravity gradient. A cold atom gravity gradiometer system includes comprising: first and second magneto-optical traps, each having a plurality of mirrored surfaces arranged to reflect an incident laser beam to trap respective first and second cold atom clouds separated from each other by a separation distance; an optical subsystem arranged to transmit a first laser beam in a first direction along a first longitudinal axis towards the first magneto-optical trap and a second laser beam in an opposite second direction along a second longitudinal axis towards the second magneto-optical trap, the second longitudinal axis being parallel to the first longitudinal axis.

Abstract: An optical frequency manipulation using an optical subsystem configured to provide a modulated laser beam for interaction with an atomic sample. The optical system may include: an optical subsystem for producing a light beam, the optical subsystem having a laser source and an IQ modulator, wherein the IQ modulator is operable to modulate light from the laser source at a carrier frequency to produce modulated light having a single sideband at a sideband frequency; and a chamber for containing an atomic sample, wherein the optical subsystem is arranged to direct the light beam towards the chamber to interact with an atomic sample contained therein.

Abstract: The disclosure relates to a gravity gradiometer including a pair of magneto-optical traps for measuring a gravity gradient. A cold atom gravity gradiometer system includes comprising: first and second magneto-optical traps, each having a plurality of mirrored surfaces arranged to reflect an incident laser beam to trap respective first and second cold atom clouds separated from each other by a separation distance; an optical subsystem arranged to transmit a first laser beam in a first direction along a first longitudinal axis towards the first magneto-optical trap and a second laser beam in an opposite second direction along a second longitudinal axis towards the second magneto-optical trap, the second longitudinal axis being parallel to the first longitudinal axis.