Atom chips are robust and extremely powerful toolboxes for quantum optical experiments, since they make it possible to create exceedingly precise magnetic traps for neutral atoms with minimal field modulations. Accurate manipulation of trapped atoms is feasible with magnetic and electric fields created on the atom chip. Therefore atom chips with high quality surfaces and extremely well defined wires were build (roughness < 20nm). Furthermore new generations of atom chips were developed, like the multi-layer atom chip with contact-free wire crossings, the sub-micron structured atom chip and the semiconducting atom chip. Extensive characterisation measurements of atom chip wires demonstrated that the wires stand current densities of up to 10^7A/cm^2 for seconds and voltage differences of more than 500V over 10µm. From the different materials tested doped silicon with a thin silicon dioxide layer is the best qualified substrate for atom chip fabrication. The atom chips fabricated during this thesis have been used in many successful experiments, yielding numerous results. Moreover this thesis established the basics for many further experiments in atom physics and quantum optics and delivers complete instructions for the fabrication of all developed atom chips as well as an introduction to the experiments.Atom chips are robust and extremely powerful toolboxes for quantum optical experiments, since they make it possible to create exceedingly precise magnetic traps for neutral atoms with minimal field modulations. Accurate manipulation of trapped atoms is feasible with magnetic and electric fields created on the atom chip. Therefore atom chips with high quality surfaces and extremely well defined wires were build (roughness < 20nm). Furthermore new generations of atom chips were developed, like the multi-layer atom chip with contact-free wire crossings, the sub-micron structured atom chip and the semiconducting atom chip. Extensive characterisation measurements of atom chip wires demonstrated that the wires stand current densities of up to 10^7A/cm^2 for seconds and voltage differences of more than 500V over 10µm. From the different materials tested doped silicon with a thin silicon dioxide layer is the best qualified substrate for atom chip fabrication. The atom chips fabricated during this thesis have been used in many successful experiments, yielding numerous results. Moreover this thesis established the basics for many further experiments in atom physics and quantum optics and delivers complete instructions for the fabrication of all developed atom chips as well as an introduction to the experiments.

Jan 1, 20063 citations

Design, microfabrication and characterization of planarized multilayer atom chips with enhanced heat dissipation

Ho‐Chiao Chuang, Chung-Wen Weng, Hsiang-Fu Li

This paper describes the design and fabrication of planarized multilayer atom chips for an ultrahigh-vacuum system in atomic physics experiments. A fabrication process is developed to define micrometer-scale wire patterns on a silicon substrate and wires are plated by copper electroplating. SU-8 is chosen as the isolation layer between the upper and bottom wires, and its thickness, surface flatness and surface roughness (Ra = 5 nm) are controlled by the chemical–mechanical planarization process. A reflectivity of nearly 90% is measured on the chip surface; thus, the former method of attaching a silver mirror is unnecessary (Du et al 2004 Phys. Rev. A 70 053606). A heat dissipation copper block is incorporated in our chip design to increase the sustainable current densities of upper wires of more than 3.8 × 105 A cm−2. Results show the improvement of 55.74%, compared with the nonheat dissipation design (2.44 × 105 A cm−2), and thus meeting the requirements for chip-based atom trapping experiments.This paper describes the design and fabrication of planarized multilayer atom chips for an ultrahigh-vacuum system in atomic physics experiments. A fabrication process is developed to define micrometer-scale wire patterns on a silicon substrate and wires are plated by copper electroplating. SU-8 is chosen as the isolation layer between the upper and bottom wires, and its thickness, surface flatness and surface roughness (Ra = 5 nm) are controlled by the chemical–mechanical planarization process. A reflectivity of nearly 90% is measured on the chip surface; thus, the former method of attaching a silver mirror is unnecessary (Du et al 2004 Phys. Rev. A 70 053606). A heat dissipation copper block is incorporated in our chip design to increase the sustainable current densities of upper wires of more than 3.8 × 105 A cm−2. Results show the improvement of 55.74%, compared with the nonheat dissipation design (2.44 × 105 A cm−2), and thus meeting the requirements for chip-based atom trapping experiments.

Journal of Micromechanics and MicroengineeringNov 3, 20118 citations

An atom chip for studying interactions between atoms and metal surfaces

J.D. Carter, Owen Cherry, J.D.D. Martin

Bulletin of the American Physical SocietyJun 7, 20070 citations

Controlling stray electric fields on an atom chip for experiments on Rydberg atoms

D. Davtyan, Shimon Machluf, Maarten L. Soudijn +4 more

Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than $0.2\phantom{\rule{0.28em}{0ex}}\mathrm{V}/\mathrm{cm}$ at $78\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.Experiments handling Rydberg atoms near surfaces must necessarily deal with the high sensitivity of Rydberg atoms to (stray) electric fields that typically emanate from adsorbates on the surface. We demonstrate a method to modify and reduce the stray electric field by changing the adsorbate distribution. We use one of the Rydberg excitation lasers to locally affect the adsorbed dipole distribution. By adjusting the averaged exposure time we change the strength (with the minimal value less than $0.2\phantom{\rule{0.28em}{0ex}}\mathrm{V}/\mathrm{cm}$ at $78\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.

arXiv:1710.05301Physical Review AFeb 22, 201812 citations

0.2\phantom{\rule{0.28em}{0ex}}\mathrm{V}/\mathrm{cm}

at $78\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$ from the chip) and even the sign of the perpendicular field component. This technique is a useful tool for experiments handling Rydberg atoms near surfaces, including atom chips.