Ultracold atoms exquisitely controlled by lasers are the quantum foundation, particularly for sensing, timekeeping, and computing, of state-of-the-art quantum science and technology. However, the laboratory-scale infrastructure for such optical-atomic quantum apparatus rarely translates into commercial applications. A promising solution is miniaturizing the optical layouts onto a chip-scale device integrated with cold atoms inside a compact ultra-high vacuum (UHV) chamber. For prototyping purposes, however, rapidly loading or exchanging test photonic devices into a UHV chamber is limited by the evacuation time from atmospheric pressures to the optimal pressures for ultracold atoms of 1 × 10-11 Torr, a process that typically takes weeks or months without cryogenics. Here, we present a loadlock apparatus and loading procedure capable of venting, exchanging, and evacuating back to <1×10-11 Torr in under 24 h. Our system allows for rapid testing and benchmarking of various photonic devices with ultracold atoms.
Ultracold atoms exquisitely controlled by lasers are the quantum foundation, particularly for sensing, timekeeping, and computing, of state-of-the-art quantum science and technology. However, the laboratory-scale infrastructure for such optical-atomic quantum apparatus rarely translates into commercial applications. A promising solution is miniaturizing the optical layouts onto a chip-scale device integrated with cold atoms inside a compact ultra-high vacuum (UHV) chamber. For prototyping purposes, however, rapidly loading or exchanging test photonic devices into a UHV chamber is limited by the evacuation time from atmospheric pressures to the optimal pressures for ultracold atoms of 1 × 10-11 Torr, a process that typically takes weeks or months without cryogenics. Here, we present a loadlock apparatus and loading procedure capable of venting, exchanging, and evacuating back to <1×10-11 Torr in under 24 h. Our system allows for rapid testing and benchmarking of various photonic devices with ultracold atoms.
Cavity quantum electrodynamics (QED), the study of the interaction between quantized emitters and photons confined in an optical cavity, is an important tool for quantum science in computing, networking, and synthetic matter. In atomic cavity QED, this approach typically relies upon an ultrahigh vacuum chamber that hosts a cold trapped atomic ensemble and an optical cavity. Upgrading the cavity necessitates a months-long laborious process of removing external optics, venting, replacing the resonator, baking, and replacing optics, constituting a substantial bottleneck to innovation in resonator design. In this work, we demonstrate that the flexibility of optical cavities and the quick turnaround time in switching between them can be restored with the vacuum loadlock technique-reducing the cycle time to install a cavity, bake it, and transport it into the science chamber for days, achieving 3 × 10-10 Torr pressure in the science chamber. By reducing vacuum limitations, this approach is particularly powerful for labs interested in quickly exploring novel optic cavities or any other atomic physics relying on in-vacuum optics.
Using matter wave interferometry to perform high precision measurements is an exciting field of modern day physics and engineering. Physical constants and anomalies too small to observe with classical devices can be probed and measured with quantum technology. The ability to control the wave nature of a specific particle opens up a vast set of methodologies engineered for the given particle. The most complete toolboxes exist for alkali metals such as rubidium and cesium. The atomic structure of strontium provides a number of advantages in further developing these methods and technologies, especially in the resolution of spectroscopic measurements.A promising method of matter-wave control utilizes optical waveguides and atomic properties to trap and guide matter waves. Using laser cooling techniques, atoms are cooled to microkelvin temperatures before being loaded onto the nanophotonic chip, thus receiving the appropriate name, atom-on-chip devices. The ability to manufacture the photonic waveguides in a multitude of different arrangements shows promise in being able to develop atomtronic devices which are equivalent to electronic devices, but utilize matter-waves of neutral atoms instead of electrons.The heart of our novel technology is an ultra-high vacuum (UHV) apparatus with sample loading capabilities. In this thesis, I discuss the design and construction of the apparatus to provide quick turn over between loading nanophotonic devices and experimental trapping by separation of the main chamber from a load lock. The ultimate pressures in both reach 3.8times10−11 and below 1times10−11 Torr and initial trials were conducted with a 36-48 hour turn over between loading a chip at atmosphere, and inserting it into the UHV main chamber. These metrics beats other groups by an order of magnitude in pressure and others week-long loading time. Continual improvements are being made to further decrease this time.
Employing compact quantum sensors in field or in space (e.g., small satellites) implies demanding requirements on components and integration technologies. Within our work on integrated sensors, we develop miniaturized, ultra-stable optical setups for optical cooling and trapping of cold atomic gases. Besides challenging demands on alignment precision, and thermo-mechanical durability, we specifically address ultra-high vacuum (UHV) compatibility of our integration technologies and optical components. A prototype design of an UHV-compatible, crossed beam optical dipole trap setup and its application within a cold atomic quantum sensor is described. First qualification efforts on adhesive micro-integration technologies are presented. These tests are conducted in application-relevant geometries and material combinations common for micro-integrated optical setups. Adhesive aging will be investigated by thermal cycling or gamma radiation exposure. For vacuum compatibility testing, a versatile UHV testing system is currently being set up, enabling residual gas analysis and measurement of total gas rates down to 5•10-10mbar l/s at a base pressure of 10-11 mbar, exceeding the common ASTM E595 test.
Employing compact quantum sensors in field or in space (e.g., small satellites) implies demanding requirements on components and integration technologies. Within our work on integrated sensors, we develop miniaturized, ultra-stable optical setups for optical cooling and trapping of cold atomic gases. Besides challenging demands on alignment precision, and thermo-mechanical durability, we specifically address ultra-high vacuum (UHV) compatibility of our integration technologies and optical components. A prototype design of an UHV-compatible, crossed beam optical dipole trap setup and its application within a cold atomic quantum sensor is described. First qualification efforts on adhesive micro-integration technologies are presented. These tests are conducted in application-relevant geometries and material combinations common for micro-integrated optical setups. Adhesive aging will be investigated by thermal cycling or gamma radiation exposure. For vacuum compatibility testing, a versatile UHV testing system is currently being set up, enabling residual gas analysis and measurement of total gas rates down to 5•10-10mbar l/s at a base pressure of 10-11 mbar, exceeding the common ASTM E595 test.
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.
Compact ultra-high vacuum systems are key enabling components for cold atom technologies, facilitating extremely accurate sensing applications. There has been important progress towards a truly portable compact vacuum system, however size, weight and power consumption can be prohibitively large, optical access may be limited, and active pumping is often required. Here, we present a centilitre-scale ceramic vacuum chamber with He-impermeable viewports and an integrated diffractive optic, enabling robust laser cooling with light from a single polarization-maintaining fibre. A cold atom demonstrator based on the vacuum cell delivers 107 laser-cooled 87Rb atoms per second, using minimal electrical power. With continuous Rb gas emission active pumping yields a 10−7mbar equilibrium pressure, and passive pumping stabilises to 3×10−6mbar, with a 17day time constant. A passively-pumped vacuum cell, with no Rb dispensing, has currently kept a similar pressure for a year. The passive-pumping vacuum lifetime is several years, estimated from short-term He throughput, with many foreseeable improvements. This technology enables wide-ranging mobilization of ultracold quantum metrology.