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 Physics , 2010, DOI: 10.1103/PhysRevA.81.052335 Abstract: A one-electron qubit would offer a new option for quantum information science, including the possibility of extremely long coherence times. One-quantum cyclotron transitions and spin flips have been observed for a single electron in a cylindrical Penning trap. However, an electron suspended in a planar Penning trap is a more promising building block for the array of coupled qubits needed for quantum information studies. The optimized design configurations identified here promise to make it possible to realize the elusive goal of one trapped electron in a planar Penning trap for the first time - a substantial step toward a one-electron qubit.
 Physics , 2006, Abstract: We present a number of alternative designs for Penning ion traps suitable for quantum information processing (QIP) applications with atomic ions. The first trap design is a simple array of long straight wires which allows easy optical access. A prototype of this trap has been built to trap Ca+ and a simple electronic detection scheme has been employed to demonstrate the operation of the trap. Another trap design consists of a conducting plate with a hole in it situated above a continuous conducting plane. The final trap design is based on an array of pad electrodes. Although this trap design lacks the open geometry of the traps described above, the pad design may prove useful in a hybrid scheme in which information processing and qubit storage take place in different types of trap. The behaviour of the pad traps is simulated numerically and techniques for moving ions rapidly between traps are discussed. Future experiments with these various designs are discussed. All of the designs lend themselves to the construction of multiple trap arrays, as required for scalable ion trap QIP.
 Physics , 2007, Abstract: We demonstrate that spin chains are experimentally feasible using electrons confined in micro-Penning traps, supplemented with local magnetic field gradients. The resulting Heisenberg-like system is characterized by coupling strengths showing a dipolar decay. These spin chains can be used as a channel for short distance quantum communication. Our scheme offers high accuracy in reproducing an effective spin chain with relatively large transmission rate.
 Physics , 2009, DOI: 10.1063/1.3276699 Abstract: We report on the design and testing of an array of Penning ion traps made from printed circuit board. The system enables fast shuttling of ions from one trapping zone to another, which could be of use in quantum information processing. We describe simulations carried out to determine the optimal potentials to be applied to the trap electrodes for enabling this movement. The results of a preliminary experiment with a cloud of laser cooled calcium ions demonstrate a round-trip shuttling efficiency of up to 75%.
 Physics , 2005, DOI: 10.1103/PhysRevA.73.032307 Abstract: Chiaverini et al. [Quant. Inf. Comput. 5, 419 (2005)] recently suggested a linear Paul trap geometry for ion trap quantum computation that places all of the electrodes in a plane. Such planar ion traps are compatible with modern semiconductor fabrication techniques and can be scaled to make compact, many zone traps. In this paper we present an experimental realization of planar ion traps using electrodes on a printed circuit board to trap linear chains of tens of 0.44 micron diameter charged particles in a vacuum of 15 Pa (0.1 torr). With these traps we address concerns about the low trap depth of planar ion traps and develop control electrode layouts for moving ions between trap zones without facing some of the technical difficulties involved in an atomic ion trap experiment. Specifically, we use a trap with 36 zones (77 electrodes) arranged in a cross to demonstrate loading from a traditional four rod linear Paul trap, linear ion movement, splitting and joining of ion chains, and movement of ions through intersections. We further propose an additional DC biased electrode above the trap which increases the trap depth dramatically, and a novel planar ion trap geometry that generates a two dimensional lattice of point Paul traps.
 Robert Bluhm Physics , 1999, Abstract: The CPT theorem has been tested to very high precision in a variety of experiments involving particles and antiparticles confined within Penning traps. These tests include comparisons of anomalous magnetic moments and charge-to-mass ratios of electrons and positrons, protons and antiprotons, and hydrogen ions and antiprotons. We present a theoretical analysis of possible signals for CPT and Lorentz violation in these systems. We use the framework of Colladay and Kosteleck\'y, which consists of a general extension of the $SU(3) \times SU(2) \times U(1)$ standard model including possible CPT and Lorentz violations arising from spontaneous symmetry breaking at a fundamental level, such as in string theory. We work in the context of an extension of quantum electrodynamics to examine CPT and Lorentz tests in Penning traps. Our analysis permits a detailed study of the effectiveness of experimental tests of CPT and Lorentz symmetry performed in Penning traps. We describe possible signals that might appear in principle, and estimate bounds on CPT and Lorentz violation attainable in present and future experiments.
 Physics , 1998, DOI: 10.1103/PhysRevD.57.3932 Abstract: A theoretical analysis is performed of Penning-trap experiments testing CPT and Lorentz symmetry through measurements of anomalous magnetic moments and charge-to-mass ratios. Possible CPT and Lorentz violations arising from spontaneous symmetry breaking at a fundamental level are treated in the context of a general extension of the SU(3) x SU(2) x U(1) standard model and its restriction to quantum electrodynamics. We describe signals that might appear in principle, introduce suitable figures of merit, and estimate CPT and Lorentz bounds attainable in present and future Penning-trap experiments. Experiments measuring anomaly frequencies are found to provide the sharpest tests of CPT symmetry. Bounds are attainable of approximately $10^{-20}$ in the electron-positron case and of $10^{-23}$ for a suggested experiment with protons and antiprotons. Searches for diurnal frequency variations in these experiments could also limit certain types of Lorentz violation to the level of $10^{-18}$ in the electron-positron system and others at the level of $10^{-21}$ in the proton-antiproton system. In contrast, measurements comparing cyclotron frequencies are sensitive within the present theoretical framework to different kinds of Lorentz violation that preserve CPT. Constraints could be obtained on one figure of merit in the electron-positron system at the level of $10^{-16}$, on another in the proton-antiproton system at $10^{-24}$, and on a third at $10^{-25}$ using comparisons of $H^-$ ions with antiprotons.
 Physics , 2008, DOI: 10.1103/PhysRevA.78.012338 Abstract: We propose a scheme to engineer an effective spin Hamiltonian starting from a system of electrons confined in micro-Penning traps. By means of appropriate sequences of electromagnetic pulses, alternated to periods of free evolution, we control the shape and strength of the spin-spin interaction. Moreover, we can modify the effective magnetic field experienced by the particle spin. This procedure enables us to reproduce notable quantum spin systems, such as Ising and XY models. Thanks to its scalability, our scheme can be applied to a fairly large number of trapped particles within the reach of near future technology.
 Physics , 1998, DOI: 10.1063/1.57442 Abstract: We present a theoretical analysis of signals for CPT and Lorentz violation in g-2 and charge-to-mass-ratio experiments on electrons and positrons in Penning traps. Experiments measuring anomaly frequencies are found to be the most sensitive to CPT violation. We find that the conventional figure of merit for CPT breaking, involving the difference of the electron and positron g factors, is inappropriate in this context, and an alternative is introduced. Bounds of approximately one part in 10^{20} are attainable.
 Physics , 2012, DOI: 10.1063/1.3685246 Abstract: Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used in unitary architectures that couple the electric and magnetic components into an integrated structure. We have constructed a two- magnet Penning trap with radial access to enable the use of laser or atomic beams, as well as the collection of light. An experimental apparatus equipped with ion optics is installed at the NIST electron beam ion trap (EBIT) facility, constrained to fit within 1 meter at the end of a horizontal beamline for transporting highly charged ions. Highly charged ions of neon and argon, extracted with initial energies up to 4000 eV per unit charge, are captured and stored to study the confinement properties of a one-magnet trap and a two-magnet trap. Design considerations and some test results are discussed.
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