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Nanostructured copper thin film used for catalysis

CARVALHO, Alexsander Tressino de; LIMA, Roberto da Rocha; SILVA, Lilian Marques; FACHINI, Estevao; SILVA, Maria Lucia Pereira da
Fonte: ELSEVIER SCIENCE SA Publicador: ELSEVIER SCIENCE SA
Tipo: Artigo de Revista Científica
Português
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Catalytic properties of copper thin films deposited in small channels and cavities were tested using Raman microscopy and mass spectroscopy (MS) techniques, mainly. The catalytic surface conditions were addressed visually and chemically by optical microscopy and X-ray photoelectron spectroscopy (XPS), respectively. The experimental conditions of present work induced copper oxidation; eventually a number of carbon species and graphite remained on the catalytic surface. Quartz crystal microbalance and mass spectroscopy data support both adsorption and catalysis phenomena. MS showed CO2 formation during n-hexane heating process but not to 2-propanol, probably due to redox reactions. XPS of copper surface present in the cavity after catalysis tests detected Cu2O and a range of possible carbon species. The adsorption and catalytic performance of copper films deposited in cavities and microchannels were quite similar. A simple miniaturized device for microanalysis was proposed. (C) 2007 Elsevier B.V. All rights reserved.

Bose-Einstein Kondensate in magnetischen Mikrofallen; Bose-Einstein Condensates in Magnetic Microtraps

Fortágh, József
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
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In der vorliegenden Arbeit wurde ein neues Konzept zur Herstellung von Bose-Einstein Kondensaten entwickelt und umgesetzt. Das Fallenpotential für ultrakalte Atome entsteht dabei an miniaturisierten Elektromagneten: an einer Mikrostruktur mit extrem dünnen Leiterbahnen bzw. an einem dünnen Draht. Die Mikrofalle wird mit einem neuartigen Lademechanismus befüllt. Dabei werden 87Rb Atome durch adiabatisches Umformen eines ausgedehnten magnetischen Fallenpotentials in die steile Geometrie der Mikrofalle überführt. Mit diesem Ladeschema ist es gelungen, die bislang größten Atomzahlen, bis zu 2x10E7 Atome, in eine Mikrofalle einzufangen und zum ersten Mal Bose-Einstein Kondensation in einer magnetischen Mikrofalle zu beobachten. Das Kondensat enthält bis zu 8x10E5 Atome. Die Miniaturisierung der Leiter ermöglichte es, Atome in die unmittelbare Nähe von Oberflächen zu bringen. In dieser Arbeit wurde zum ersten Mal eine systematische Untersuchung der Wechselwirkungen zwischen ultrakalten Atomen und der Mikrofallenoberfläche vorgenommen. Es wurden Messungen zur Lebensdauer und zu Heizraten durchgeführt. Während die Lebensdauer der Wolke bei der Annäherung an die Oberfläche abnimmt, hängen die Heizraten nur von den Fallenfrequenzen ab. In steilen Mikrofallen mit Frequenzen im kHz-Bereich wurde selbst in Oberflächennähe kein relevantes Heizen beobachtet. Als weiteres wesentliches Resultat wurde ein neuer magnetischer Effekt an stromdurchflossenen Leitern entdeckt. Die Dichteverteilung der Atome in langgestreckten Fallen parallel zu den Leiterbahnen zeigt eine räumlich periodische Struktur. Die Strukturierung mit einer Periode von 200–300 mm tritt allgemein in Mikrofallenexperimenten an Kupferleitern auf. Es zeigte sich...

Dynamik von Bose-Einstein-Kondensaten in anharmonischen Wellenleitern; Dynamics of Bose-Einstein Condensates in Anharmonic Waveguides

Ott, Herwig
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
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In dieser Arbeit wird eine systematische Untersuchung zur Dynamik eines Bose-Einstein-Kondensats in einem anharmonischen Wellenleiter vorgestellt. Dazu wurde eine Apparatur zur Erzeugung von Bose-Einstein-Kondensaten in magnetischen Mikrofallen aufgebaut. Der experimentelle Aufbau ist gekennzeichnet durch ein einfaches, effizientes Ladesystem der magnetooptischen Falle, bestehend aus einer gepulsten, thermischen Quelle für Rubidiumatome. Alle magnetfelderzeugenden Komponenten für die Manipulation der Atome befinden sich als kompakte Einheit direkt im Vakuum. Ein neuartiges Tr ansferprinzip, mit dem die Atome in die Mikrofalle überführt werden, w ird in dieser Arbeit ausführlich beschrieben. Die Mikrofalle wird mit mikro fabrizierten Kupferleiterbahnen auf einem Keramiksubstrat erzeugt. Zur Untersuch ung der Dynamik des Kondensates wurde dessen Schwingung in einem anharmonischen Wellenleiter analysiert. Das Kondensat erfährt eine starke Kopplung der Sch werpunktsbewegung mit der internen Dynamik des Kondensats. Dabei werden die nied erfrequenten kollektiven Moden (Formschwingungen) des Kondensats angeregt. Wegen der Anharmonizität zeigt das Spektrum der Schwerpunktsbewegung Vielfache d er Grundfrequenz. Die Schwerpunktsbewegung ist nahezu ungedämpft und weist eine außerordentlich hohe Güte von 20000 auf. Die Ausdehnung des Kond ensats ändert sich bei den angeregten Formschwingungen um bis zu einem Fakt or 10 und wegen der nichtlinearen Wechselwirkung des Kondensats tritt zusät zlich Frequenzmischung der kollektiven Anregungen auf. Die experimentellen Daten werden mit einem theoretischen Modell beschrieben...

Sympathetisches Kühlen von 6Lithium mit 87Rubidium; Sympathetic cooling of 6Lithium with 87Rubidium

Silber, Christian
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
16.7%
Gegenstand der vorliegenden Arbeit ist die Entwicklung einer Apparatur zur simultanen Präparation von ultrakaltem 87Rubidium und 6Lithium. Besonderer Wert wurde dabei auf Zuverlässigkeit und Langzeitstabilität der einzelnen Komponenten gelegt. Durch diese weltweit einzigartige Experimentieranlage war es jetzt erstmals möglich, 6Lithium durch 87Rubidium sympathetisch ins entartete Regime zu kühlen. Die so präparierbaren Quantengase sind ein exzellenter Ausgangspunkt für künftige Untersuchungen. Der erste Teil dieser Arbeit widmet sich grundsätzlichen Überlegungen zu Magnetfallen. Kapitel 2 stellt verschiedene Methoden zur Berechnung und Näherung der Magnetfelder felderzeugender Elemente vor, die in die Entwicklung einer Simulations-Toolbox (Anhang B) für Magnetfelder auf der Basis von Mathematica und der Programmiersprache C eingeflossen sind. Insbesondere ein Potenzreihenansatz für zylinder- und ebenensymmetrische Felder dient dann in Kapitel 3 zu grundsätzlichen Überlegungen zum Design von Magnetfallen. Verschiedene Typen der Magnetfalle werden untersucht und hinsichtlich Feldgeometrie, Fallentiefe, Lebensdauer der gespeicherten Atome und Aspektverhältnis verglichen. Kapitel 4 diskutiert den auf der Basis der Erkenntnisse der ersten beiden Kapitel entwickelten Aufbau in unserem Experiment. Besonderes Augenmerk liegt auf der neuartigen Doppeldraht-Ioffefalle...

Manipulation und Kontrolle von Flussquanten in Supraleitern durch maßgeschneiderte Haftzentren; Manipulation and Control of Flux Quanta in Superconductors by Tailored Pinning Sites

Kemmler, Matthias
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
16.7%
In der vorliegenden Arbeit wurden quantisierte Flusswirbel (Vortices) in Supraleitern untersucht, wobei diese Flusswirbel mit Hilfe von Nanostrukturen gezielt in ihren statischen und dynamischen Eigenschaften manipuliert und kontrolliert werden sollten. Durch das Einbringen von künstlichen Haftzentren (Pinningzentren) in Form von (sub-)Mikrolöchern (Antidots) ist es möglich die Bewegung von Abrikosov-Flusswirbeln zu verhindern bzw. zu kontrollieren und somit insbesondere den maximalen (kritischen) Suprastrom zu erhöhen. Hierbei hat die Anordnung der Antidots beträchtliche Auswirkungen auf den Magnetfeldbereich, in welchem der kritische Strom des Supraleiters eine Erhöhung zeigt. Ein aktuelles Forschungsgebiet im Bereich der Supraleitung beschäftigt sich mit der (anwendungsorientierten) Fragestellung der optimalen Anordnung von Pinningzentren. Im Rahmen der Arbeit wurde eine Methode zur Herstellung von Nb-Filmen mit Antidots entwickelt. Die Kombination von Elektronenstrahllithographie und Lift-Off Prozess erlaubte die Variation der Geometrie und der Anordnung der Antidots im Submikrometerbereich. Es wurden Nb-Filme ohne Antidots, Filme mit zufällig verteilten Antidots und Filme mit periodischen, bzw. zufällig verdünnten periodischen und quasiperiodischen Antidots (Antidot-Arrays) untersucht. Wesentliche Verbesserungen an dem (selbst aufgebauten) Messsystem ermöglichten die Durchführung der in dieser Arbeit vorgestellten elektrischen Transportmessungen. Messungen des kritischen Stroms in Abhängigkeit des angelegten Magnetfeldes an Nb-Filmen mit Arrays aus kreisrunden Antidots zeigten ausgeprägte Kommensurabilitätseffekte (Matchingeffekte) des Vortexgitters mit den Antidot-Arrays nahe der kritischen Temperatur. In Messungen an quasiperiodischen 5-faltigen Penrose-Antidot-Arrays konnten erstmals Matchingeffekte und damit die Ausbildung eines quasiperiodischen Vortexgitters nachgewiesen werden. Zudem konnte gezeigt werden...

Meissner effect in superconducting microtraps; Meissner-Effekt in supraleitenden Microfallen

Cano, Daniel
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
17.67%
This thesis investigates the impact of the Meissner effect on magnetic microtraps for ultracold atoms near superconducting microstructures. This task has been accomplished both theoretically and experimentally. The Meissner effect distorts the magnetic fields near superconducting surfaces, thus altering the parameters of magnetic microtraps. Both computer simulations and experimental measurements demonstrate that the Meissner effect shortens the distance between the magnetic microtrap and the superconducting surface, reduces the magnetic-field gradients and dramatically lowers the trap depth. A novel numerical method for calculating magnetic fields in atom chips with superconducting microstructures has been developed. This numerical method overcomes the geometrical limitations of other calculation techniques and can solve superconducting microstructures of arbitrary geometry. The numerical method has been used to calculate the parameters of magnetic microtraps in computer-simulated chips containing thin-film wires. Simulations were carried out for both the superconducting and the normal-conducting state, and the differences between the two cases were analyzed. Computer simulations have been contrasted with experimental measurements. The experimental apparatus generates a magnetic microtrap for ultracold Rubidium atoms near a superconducting Niobium wire of circular cross section. The design and construction of the apparatus has met the challenge of integrating the techniques for producing atomic quantum gases with the techniques for cooling solid bodies to cryogenic temperatures. By monitoring the position of the atom cloud...

Interfacing cold atoms and superconductors; Ultrakalte Atome in supraleitenden Mikrofallen

Hattermann, Helge
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
16.7%
One of the major challenges of the last decade in physics has been the practical implementation of quantum computing. One very promising candidate for this task are processors using superconducting qubits. While superconducting circuits working in the quantum regime can process quantum information at high rates, they lack the ability to store quantum information on timescales which are longer than a few microseconds. Unfortunately, there is no single quantum system which fulfills all the criteria for a quantum computer. It is therefore very interesting to combine two different quantum systems in order to exploit their respective advantages. This thesis describes a path towards constructing a hybrid quantum system of ultracold atoms and superconducting microstructures. The ultimate goal of this is a hybrid system in which quantum information is processed by superconducting qubits, transferred using a superconducting coplanar microwave resonator and stored in an ensemble of cold rubidium-87 atoms. The experimental system used to pursue this goal combines a cold atom setup at room temperature with a helium flow cryostat, which is used to cool superconducting structures to a temperature of 4.2 K. Atoms are prepared and trapped in magnetic potentials created by currents in a superconducting microtrap. We study the influence of the Meissner effect on the magnetic field...

Efficient collisional blockade loading of single atom into a tight microtrap

Fung, Y. H.; Andersen, M. F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/06/2015 Português
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27.33%
We show that controlled inelastic collisions can improve the single atom loading efficiency in the collisional blockade regime of optical microtraps. A collisional loss process where only one of the colliding atoms are lost, implemented during loading, enables us to kick out one of the atoms as soon as a second atom enters the optical microtrap. When this happens faster than the pair loss, which has limited the loading efficiency of previous experiments to about 50%, we experimentally observe an enhancement to 80%. A simple analytical theory predicts the loading dynamics. Our results opens up an efficient and fast route for loading individual atoms into optical tweezers and arrays of microtraps that are too tight for easy implementation of the method reported in [1,2]. The loading of tight traps with single atoms is a requirement for their applications in future experiments in quantum information processing and few-body physics.; Comment: 16 pages, 7 figures

Meissner effect in superconducting microtraps

Cano, D.; Kasch, B.; Hattermann, H.; Kleiner, R.; Zimmermann, C.; Koelle, D.; Fortágh, J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/08/2008 Português
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We report on the realization and characterization of a magnetic microtrap for ultra cold atoms near a straight superconducting Nb wire with circular cross section. The trapped atoms are used to probe the magnetic field outside the superconducting wire. The Meissner effect shortens the distance between the trap and the wire, reduces the radial magnetic-field gradients and lowers the trap depth. Measurements of the trap position reveal a complete exclusion of the magnetic field from the superconducting wire for temperatures lower than 6K. As the temperature is further increased, the magnetic field partially penetrates the superconducting wire; hence the microtrap position is shifted towards the position expected for a normal-conducting wire.; Comment: 5 pages, 4 figures

Microtrap arrays on magnetic film atom chips for quantum information science

Leung, V. Y. F.; Tauschinsky, A.; van Druten, N. J.; Spreeuw, R. J. C.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/04/2011 Português
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We present two different strategies for developing a quantum information science platform, based on our experimental results with magnetic microtrap arrays on a magnetic-film atom chip. The first strategy aims for mesoscopic ensemble qubits in a lattice of ~5 {\mu}m period, so that qubits can be individually addressed and interactions can be mediated by Rydberg excitations. The second strategy aims for direct quantum simulators using sub-optical lattices of ~100 nm period. These would allow the realization of condensed matter inspired quantum many-body systems, such as Hubbard models in new parameter regimes. The two approaches raise quite different issues, some of which are identified and discussed.; Comment: 10 pages, 6 figures, submitted to special issue "Quantum Information with Neutral Particles" of "Quantum Information Processing"

Laserless trapped-ion quantum simulations without spontaneous scattering using microtrap arrays

Chiaverini, J.; Lybarger Jr, W. E.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.33%
We propose an architecture and methodology for large-scale quantum simulations using hyperfine states of trapped-ions in an arbitrary-layout microtrap array with laserless interactions. An ion is trapped at each site, and the electrode structure provides for the application of single and pairwise evolution operators using only locally created microwave and radio-frequency fields. The avoidance of short-lived atomic levels during evolution effectively eliminates errors due to spontaneous scattering; this may allow scaling of quantum simulators based on trapped ions to much larger systems than currently estimated. Such a configuration may also be particularly appropriate for one-way quantum computing with trapped-ion cluster states.; Comment: 12 pages, 5 figures, edited typos, added refs and text for clarification to reflect published version

Cold atom gas at very high densities in an optical surface microtrap

Hammes, M.; Rychtarik, D.; Nägerl, H. -C.; Grimm, R.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/04/2002 Português
Relevância na Pesquisa
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An optical microtrap is realized on a dielectric surface by crossing a tightly focused laser beam with an horizontal evanescent-wave atom mirror. The nondissipative trap is loaded with $\sim$$10^5$ cesium atoms through elastic collisions from a cold reservoir provided by a large-volume optical surface trap. With an observed 300-fold local increase of the atomic number density approaching $10^{14}{\rm cm}^{-3}$, unprecedented conditions of cold atoms close to a surface are realized.

Synthetic Gauge Fields for Vibrational Excitations of Trapped ions

Bermudez, A.; Schaetz, T.; Porras, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.67%
The vibrations of a collection of ions in a microtrap array can be described in terms of hopping phonons. We show theoretically that the vibrational couplings may be tailored by using a gradient of the microtrap frequencies, together with a periodic driving of the trapping potential. These ingredients allow us to induce effective gauge fields on the vibrational excitations, such that phonons mimic the behavior of charged particles in a magnetic field. In particular, microtrap arrays are ideally suited to realize the famous Aharonov-Bohm effect, and observe the paradigmatic edge states typical from quantum-Hall samples and topological insulators.; Comment: replaced with published version

Efficient loading and cooling in a dynamic optical evanescent-wave microtrap

Domokos, Peter; Ritsch, Helmut
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/02/2001 Português
Relevância na Pesquisa
27.33%
We calculate the loading efficiency and cooling rates in a bichromatic optical microtrap, where the optical potentials are generated by evanescent waves of cavity fields at a dielectric-vacuum interface. The cavity modified nonconservative dynamic light forces lead to efficient loading of the atoms as well as cooling without the need for spontaneous emission. Steady-state temperatures well below the trap depth, reaching the motional quantum regime, yield very long capturing times for a neutral atom.; Comment: Submitted to Europhysics Letters

An all-optical ion-loading technique for scalable microtrap architectures

Hendricks, R. J.; Grant, D. M.; Herskind, P. F.; Dantan, A.; Drewsen, M.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/05/2007 Português
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27.33%
An experimental demonstration of a novel all-optical technique for loading ion traps, that has particular application to microtrap architectures, is presented. The technique is based on photo-ionisation of an atomic beam created by pulsed laser ablation of a calcium target, and provides improved temporal control compared to traditional trap loading methods. Ion loading rates as high as 125 ions per second have so far been observed. Also described are observations of trap loading where Rydberg state atoms are photo-ionised by the ion Doppler cooling laser.; Comment: 8 pages, 9 figures

Simulation studies of the behavior of positrons in a microtrap with long aspect ratio

Narimannezhad, Alireza; Baker, Christopher J.; Weber, Marc H.; Xu, Jia; Lynn, Kelvin G.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.67%
The charged particles storage capacity of microtraps (micro-Penning-Malmberg traps) with large length to radius aspect ratios and radii of the order of tens of microns was explored. Simulation studies of the motions of charged particles were conducted with particle-in-cell WARP code and the Charged Particle Optics (CPO) program. The new design of the trap consisted of an array of microtraps with substantially lower end electrodes potential than conventional Penning-Malmberg traps, which makes this trap quite portable. It was computationally shown that each microtrap with 50 micron radius stored positrons with a density (1.6x10^11 cm^-3) even higher than that in conventional Penning-Malmberg traps (about 10^11 cm^-3) while the confinement voltage was only 10 V. It was presented in this work how to evaluate and lower the numerical noise by controlling the modeling parameters so the simulated plasma can evolve toward computational equilibrium. The local equilibrium distribution, where longitudinal force balance is satisfied along each magnetic field line, was attained in time scales of the simulation for plasmas initialized with a uniform density and Boltzmann energy distribution. The charge clouds developed the expected radial soft edge density distribution and rigid rotation evolved to some extent. To reach global equilibrium (i.e. rigid rotation) longer runs are required. The plasma confinement time and its thermalization were independent of the length. The length-dependency...

Trapped-Atom-Interferometer in a Magnetic Microtrap

Hänsel, W.; Reichel, J.; Hommelhoff, P.; Hänsch, T. W.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/06/2001 Português
Relevância na Pesquisa
27.67%
We propose a configuration of a magnetic microtrap which can be used as an interferometer for three-dimensionally trapped atoms. The interferometer is realized via a dynamic splitting potential that transforms from a single well into two separate wells and back. The ports of the interferometer are neighboring vibrational states in the single well potential. We present a one-dimensional model of this interferometer and compute the probability of unwanted vibrational excitations for a realistic magnetic potential. We optimize the speed of the splitting process in order suppress these excitations and conclude that such interferometer device should be feasible with currently available microtrap technique.; Comment: 6 pages, 6 figures, submitted to PRA

Thermally induced spin flips above an atom chip

Jones, M. P. A.; Vale, C. J.; Sahagun, D.; Hall, B. V.; Hinds, E. A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.33%
We describe an experiment in which Bose-Einstein condensates and cold atom clouds are held by a microscopic magnetic trap near a room temperature metal wire 500 $\mu$m in diameter. The ensemble of atoms breaks into fragments when it is brought close to the ceramic-coated aluminum surface of the wire, showing that fragmentation is not peculiar to copper surfaces. The lifetime for atoms to remain in the microtrap is measured over a range of distances down to $27 \mu$m from the surface of the metal. We observe the loss of atoms from the microtrap due to spin flips. These are induced by radio-frequency thermal fluctuations of the magnetic field near the surface, as predicted but not previously observed.; Comment: 4 pages, 4 figures

Sideband cooling and coherent dynamics in a microchip multi-segmented ion trap

Schulz, Stephan; Poschinger, Ulrich; Ziesel, Frank; Schmidt-Kaler, Ferdinand
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.33%
Miniaturized ion trap arrays with many trap segments present a promising architecture for scalable quantum information processing. The miniaturization of segmented linear Paul traps allows partitioning the microtrap in different storage and processing zones. The individual position control of many ions - each of them carrying qubit information in its long-lived electronic levels - by the external trap control voltages is important for the implementation of next generation large-scale quantum algorithms. We present a novel scalable microchip multi-segmented ion trap with two different adjacent zones, one for the storage and another dedicated for the processing of quantum information using single ions and linear ion crystals: A pair of radio-frequency driven electrodes and 62 independently controlled DC electrodes allows shuttling of single ions or linear ion crystals with numerically designed axial potentials at axial and radial trap frequencies of a few MHz. We characterize and optimize the microtrap using sideband spectroscopy on the narrow S1/2 <-> D5/2 qubit transition of the 40Ca+ ion, demonstrate coherent single qubit Rabi rotations and optical cooling methods. We determine the heating rate using sideband cooling measurements to the vibrational ground state which is necessary for subsequent two-qubit quantum logic operations. The applicability for scalable quantum information processing is proven.; Comment: 17 pages...

Dynamics of two atoms undergoing light-assisted collisions in an optical microtrap

Sompet, P.; Carpentier, A. V.; Fung, Y. H.; McGovern, M.; Andersen, M. F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/10/2013 Português
Relevância na Pesquisa
27.33%
We study the dynamics of atoms in optical traps when exposed to laser cooling light that induces light-assisted collisions. We experimentally prepare individual atom pairs and observe their evolution. Due to the simplicity of the system (just two atoms in a microtrap) we can directly simulate the pair's dynamics, thereby revealing detailed insight into it. We find that often only one of the collision partners gets expelled, similar to when using blue detuned light for inducing the collisions. This enhances schemes for using light-assisted collisions to prepare individual atoms and affects other applications as well.