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The confinement and control of atomic clouds, at temperatures measured in nanokelvin, has become a valuable tool for physicists. As a source of new physics, development of cooling techniques has led to innovative new ways to probe the nature of reality. Of particular note are experiments carried out on new and exotic states of matter such as the Bose-Einstein condensate, unseen before the advent of these techniques. Likewise, the potential for applications outside of the lab is extensive and encompasses navigation, timekeeping, quantum communication and quantum computing. Manipulating cold atoms in the presence of a so-called ‘atom chip’ (a millimetre-scale electronic device) is currently considered the future of miniaturising these experiments and measurements, but since they still require precisely locked and stabilised lasers and predominantly must take place in the ultra-high vacuum regime, quantum control relies on an extensive and well-established infrastructure of optics, electronics, vacuum chambers and pumps. This encumbrance has slowed down the transition from chip-in-a-lab experiments to lab-on-a-chip technologies. This thesis is an account of work carried out in the development of enabling technologies which will accelerate this transition, including details of prototype devices made using established semiconductor and MEMS planar fabrication techniques. The construction and testing of an apparatus for anodically and eutectically bonding die-scale samples in ultra-high vacuum is described, along with an analysis and characterisation of some of its products.

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 $^{85}\mathrm{Rb}\,5S_{1/2}\rightarrow5P_{3/2}, F=3\rightarrow F^{\prime}=4$ using sub-Doppler pump probe spectroscopy and also demonstrate excellent agreement between the measured signal and a theoretical model.

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 miniatur- ized 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, Comment: 23 pages, 10 figures