We develop an intuitive model of 2D microwave near-fields in the unusual regime of centimeter waves localized to tens of microns. Close to an intensity minimum, a simple effective description emerges with five parameters which characterize the strength and spatial orientation of the zero and first order terms of the near-field, as well as the field polarization. Such a field configuration is realized in a microfabricated planar structure with an integrated microwave conductor operating near 1 GHz. We use a single 9 Be + ion as a high-resolution quantum sensor to measure the field distribution through energy shifts in its hyperfine structure. We find agreement with simulations at the sub-micron and few-degree level. Our findings give a clear and general picture of the basic properties of oscillatory 2D near-fields with applications in quantum information processing, neutral atom trapping and manipulation, chip-scale atomic clocks, and integrated microwave circuits.PACS numbers: 03.67. Bg, 03.67.Lx, 37.10.Rs, 37.10.Ty, 37.90.+j Static or oscillatory electromagnetic fields have important applications in atomic and molecular physics for atom trapping and manipulation. Neutral atoms can be trapped in static magnetic fields in different types of magnetic traps [1]. Atomic ions can be trapped either in superpositions of static and oscillatory electric fields (Paul trap) or in superimposed static electromagnetic fields (Penning trap) [2]. Atom and molecule decelerators rely on the distortion of atomic energy levels by spatially inhomogeneous fields [3]. Common to all of these field configurations is that their basic properties can be well described in terms of static solutions to the field equations and that the behavior of the field near its intensity minimum is often critical to the application. Prominent examples include Majorana losses in neutral atom magnetic traps [1] and micromotion in Paul traps [4].Recently, motivated by advances in microfabricated atom traps, interest has grown in microwave near-fields which originate from microfabricated structures. Dimensions are typically small compared to the wavelength, but for the relatively high frequencies involved, eddy currents and phase effects become important, and the resulting field patterns are much richer than in the quasistatic case. Examples include rf potentials for neutral atoms [5] with applications in atom interferometry, quantum gates [6,7] and chip-scale atomic clocks [8] as well as microwave near-fields for trapped-ion quantum logic [9][10][11]. Also, neutral atomic clouds [12] and single ions [13] have been used to characterise near-fields at sub-mm length scales or measure magnetic field gradients [14]. The behavior of these high-frequency oscillatory fields may also become relevant for coupling atomic and molecular quantum systems to microwave circuits in the quantum regime [15,16]. Of particular importance in this context are 2D field configurations which can be realized e. g. in integrated waveguides. Notwithstanding the strong experimental int...

We present a novel ion trap fabrication method enabling the realization of multilayer ion traps scalable to an in principle arbitrary number of metal-dielectric levels. We benchmark our method by fabricating a multilayer ion trap with integrated three-dimensional microwave circuitry. We demonstrate ion trapping and microwave control of the hyperfine states of a laser cooled 9 Be + ion held at a distance of 35 m m above the trap surface. This method can be used to implement large-scale ion trap arrays for scalable quantum information processing and quantum simulation.

We present a multilayer surface-electrode ion trap with embedded 3D microwave circuitry for implementing entangling quantum logic gates. We discuss the electromagnetic full-wave simulation procedure that has led to the trap design and the characterization of the resulting microwave field-pattern using a single ion as a local field probe. The results agree with simulations within the uncertainty; compared to previous traps, this design reduces detrimental AC Zeeman shifts by three orders of magnitude. The design presented here can be viewed as an entangling gate component in a library for surface-electrode ion traps intended for quantum logic operations.