Experiments using laser cooled atoms and ions show real promise for practical applications in quantumenhanced 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 microlitre 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.PACS numbers: 07.07.Df, 37.10.Gh, 07.30.Kf, I. ULTRACOLD QUANTUM TECHNOLOGYSince the first demonstrations of atoms and ions at sub-millikelvin temperatures in the mid-1980s, the field of atomic physics has been revolutionized by laser cooling and trapping as it provides researchers with a method to probe some of the purest and sensitive quantum systems available. This field is still highly productive and recently has put significant emphasis on the practical applications of this technology beyond the laboratory 1,2 . It was evident very early on that ultracold matter would be an indispensable tool in precise timing applications and a recent demonstration 3 has shown extremely low instabilities at the 10 −18 level. The wavelike nature of atoms as they are cooled to lower temperatures can be used to form atomic interferometers that outperform optical counterparts in measurements of accelerated reference frames 4-7 , which are important for inertial guidance systems, but can also provide sensitive measurements of mass, charge and magnetic fields [8][9][10][11] . Greater sensitivity beyond the classical limit is possible via squeezed 12 and entangled states 13-15 , which are also fundamental attributes for quantum computing 16,17 , and long distance quantum networking 18 . Ultracold matter has been used in the emerging field of quantum simulation 19 and is an indispensable tool in determining fundamental constants 20 , testing general relativity 21 and defining measurement standards 22 . Many researchers and industries believe such tools will be a major part of the 'second quantum revolution' in which the more 'exotic' properties of quantum physics are applied for practical applications 23,24 .The field of ultracold matter has reached a matua) m.d.himsworth@soton.ac.uk rity in both experimental methods and theoretical understanding allowing experiments to begin leaving the laboratory 25-27 . These systems are bespoke, rarely take up a ...

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 (<75 kg) and power (∼320 W), it is the smallest package to date which is designed to load Sr atoms into an optical lattice. It consists of an ultra-high vacuum assembly (<4 L), lasers, magnetic field coils & optics required for cooling & trapping as well as a module for imaging & detection. The package can routinely produce ultra cold and dense samples of 1.6 × 105 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.

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 Rb 5S → 5P, F = 3 → F' = 4 using sub-Doppler pump probe spectroscopy and also demonstrate excellent agreement between the measured signal and a theoretical model.

No abstract

No abstract