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An atomics package is the heart of any atom based quantum sensing device. Here we report on the realisation of a field deployable atomics package for alkaline earth atoms, e.g. Sr or Yb. In terms of size (∼121 L), weight (smallest package to date which is designed to load Sr atoms into an optical lattice. It consists of an ultra-high vacuum assembly (5 88Sr atoms trapped in a 1D optical lattice in less than a second. Its robustness has been demonstrated by conducting two transportation campaigns within out-of-the-lab environments. This advancement will have impact not only on transportable optical clock development but also will influence the wider areas of quantum science and technologies, particularly requiring field deployable cold atom based quantum sensors.

We describe the application of displaced, or misaligned, beams in a mirror-based magneto-optical trap (MOT) to enable portable and miniaturized atom chip experiments, where optical access is limited to a single window. Two different geometries of beam displacement are investigated: a variation on the well-known 'vortex-MOT', and the other a novel 'hybrid-MOT' combining Zeeman-shifted and purely optical scattering force components. The beam geometry is obtained similar to the mirror-MOT, using a planar mirror surface but with a different magnetic field geometry more suited to planar systems. Using these techniques, we have trapped around 6$\times 10^6$ and 26$\times 10^6$atoms of $^{85}$Rb in the vortex-MOT and hybrid-MOT respectively. For the vortex-MOT the atoms are directly cooled well below the Doppler temperature without any additional sub-Doppler cooling stage, whereas the temperature of the hybrid-MOT has been measured slightly above the Doppler temperature limit. In both cases the attained lower temperature ensures the quantum behaviour of the trapped atoms required for the applications of portable quantum sensors and many others., Comment: Quantum Technology

The development of a portable strontium lattice clock is discussed. Solutions to many of the engineering challenges required to build the next generation of portable and ultraprecise clocks will be presented. In particular, a) the realisation of a compact laser module which produces multiple stable laser frequencies required for the experiment and b) the progress made in the development of the atomics module.

Atomic clocks have been in common use since the 1950s and over this period the clock community has had two main goals: increasing the performance of the clocks and increasing their portability. At Birmingham we aim to compress a strontium optical lattice clock, a clock with an extremely high accuracy, into a portable package. Many novel approaches need to be employed to allow such a clock to operate with a favorable SWaP while maintaining the low instability and uncertainty that makes optical clocks a desirable frequency standard. The focus of this work is to use laser activation of a strontium compound as the atomic source for the clock. Previously work published by this group [1] demonstrated that it is possible to release the strontium atoms from strontium oxide successfully load a magneto-optical trap (MOT).

We report on progress in the development of subsystem-level devices which serve as building blocks for the next generation of portable atomic clocks. Specifically, we discuss the engineering of small, low-power, low-temperature strontium vapour dispensers and a compact optical resonator useful for the stabilisation of multiple lasers.

The stabilization of lasers to absolute frequency references is a fundamental requirement in several areas of atomic, molecular and optical physics. A range of techniques are available to produce a suitable reference onto which one can 'lock' the laser, many of which depend on the specific internal structure of the reference or are sensitive to laser intensity noise. We present a novel method using the frequency modulation of an acousto-optic modulator's carrier (drive) signal to generate two spatially separated beams, with a frequency difference of only a few MHz. These beams are used to probe a narrow absorption feature and the difference in their detected signals leads to a dispersion-like feature suitable for wavelength stabilization of a diode laser. This simple and versatile method only requires a narrow absorption line and is therefore suitable for both atomic and cavity based stabilization schemes. To demonstrate the suitability of this method we lock an external cavity diode laser near the

Experiments using laser cooled atoms and ions show real promise for practical applications in quantum-enhanced metrology, timing, navigation, and sensing as well as exotic roles in quantum computing, networking, and simulation. The heart of many of these experiments has been translated to microfabricated platforms known as atom chips whose construction readily lend themselves to integration with larger systems and future mass production. To truly make the jump from laboratory demonstrations to practical, rugged devices, the complex surrounding infrastructure (including vacuum systems, optics, and lasers) also needs to be miniaturized and integrated. In this paper we explore the feasibility of applying this approach to the Magneto-Optical Trap; incorporating the vacuum system, atom source and optical geometry into a permanently sealed micro-litre system capable of maintaining 10(-10) mbar for more than 1000 days of operation with passive pumping alone. We demonstrate such an engineering challenge is achievable using recent advances in semiconductor microfabrication techniques and materials.