An optical trap for trapping and cooling atoms, the optical trap comprising: a vacuum chamber operable to provide a vacuum atmosphere in which atoms of an atomic species can be laser cooled via excitation of an electronic transition of the atomic species, referred to as the cooling transition; a laser source configured to generate first to sixth beams of laser light of respective first to sixth beam widths, the beams all having a frequency that is detuned below the frequency of the cooling transition; an optical arrangement configured to: direct the first, second and third beams to propagate across the vacuum chamber along respective first, second and third incident beam paths that deviate from a mutually orthogonal arrangement in which they would each form an alignment angle of 45° to a reference axis, having instead respective first, second and third alignment angles of between 5° and 40° to the reference axis; and direct the fourth, fifth and sixth beams to propagate across the vacuum chamber approximately along the beam paths of the first, second and third beams respectively but in opposite propagation directions to form three counter-propagating beam pairs, the beams of each counter-propagating beam pair deviating from respective paths in which their beam paths would be coincident by respective first, second and third misalignement angles (α, β, γ), the first, second and third misalignment angles and the first to sixth beam widths having values that define a volume of intersection within the vacuum chamber traversed by all of the first to sixth beams. a vacuum chamber operable to provide a vacuum atmosphere in which atoms of an atomic species can be laser cooled via excitation of an electronic transition of the atomic species, referred to as the cooling transition; a laser source configured to generate first to sixth beams of laser light of respective first to sixth beam widths, the beams all having a frequency that is detuned below the frequency of the cooling transition; an optical arrangement configured to: direct the first, second and third beams to propagate across the vacuum chamber along respective first, second and third incident beam paths that deviate from a mutually orthogonal arrangement in which they would each form an alignment angle of 45° to a reference axis, having instead respective first, second and third alignment angles of between 5° and 40° to the reference axis; and direct the fourth, fifth and sixth beams to propagate across the vacuum chamber approximately along the beam paths of the first, second and third beams respectively but in opposite propagation directions to form three counter-propagating beam pairs, the beams of each counter-propagating beam pair deviating from respective paths in which their beam paths would be coincident by respective first, second and third misalignement angles (α, β, γ), the first, second and third misalignment angles and the first to sixth beam widths having values that define a volume of intersection within the vacuum chamber traversed by all of the first to sixth beams. direct the first, second and third beams to propagate across the vacuum chamber along respective first, second and third incident beam paths that deviate from a mutually orthogonal arrangement in which they would each form an alignment angle of 45° to a reference axis, having instead respective first, second and third alignment angles of between 5° and 40° to the reference axis; and direct the fourth, fifth and sixth beams to propagate across the vacuum chamber approximately along the beam paths of the first, second and third beams respectively but in opposite propagation directions to form three counter-propagating beam pairs, the beams of each counter-propagating beam pair deviating from respective paths in which their beam paths would be coincident by respective first, second and third misalignement angles (α, β, γ), the first, second and third misalignment angles and the first to sixth beam widths having values that define a volume of intersection within the vacuum chamber traversed by all of the first to sixth beams.