[PDF] Integrated Chips And Optical Cavities For Trapped Ion Quantum Information Processing eBook

Author :
Publisher :
Page : pages
File Size : 24,74 MB
Release : 2003
Category :
ISBN :

GET BOOK

By David R. Leibrandt.

Author : David R. Leibrandt
Publisher :
Page : 169 pages
File Size : 40,44 MB
Release : 2009
Category :
ISBN :

GET BOOK

(cont.) Cavity cooling is demonstrated for the first time with trapped ions, and for the first time in the parameter regime where cooling to the motional ground state is possible. The measured cavity cooling dynamics are found to agree with a rate equation model without any free parameters. The third and final part of the thesis presents a theoretical proposal for interconversion between single trapped ion qubits and single photon qubits for quantum communication. The idea is to map the state of the single ion qubit to a superradiant collective state of several ions, which then couples strongly with single photons in an optical cavity.

Author : Tony Hyun Kim
Publisher :
Page : 187 pages
File Size : 30,87 MB
Release : 2011
Category :
ISBN :

GET BOOK

The trapped-ion quantum computer is an atom-based implementation of a quantum computer that has successfully demonstrated numerous quantum algorithms and the potential for scalability. Fundamental to its operation is the short-range Coulombic interaction among its atomic ion registers, which has led to the development of local, single-chip devices. In this work, we demonstrate the integration of an optical-fiber with a planar ion trap, and show the physical interaction between fiber light and the trapped-ion qubit. As the single-mode fiber is well-suited to the transport of single photons, the fiber interface (when augmented by an optical cavity) represents a means to link distantly located quantum computers through a common optical network. Hence, this work represents a step towards the paradigm of distributed quantum computing: self-contained, technically-simple processors may be optically linked together to perform large-scale quantum computation. This thesis is divided into two parts. In the first, we provide a thorough review of ion trap design and a detailed numerical analysis of trapped-ion motion. This theoretical discussion culminates with the development of an electronic technique that permits the arbitrary, in situ positioning of a trapped atom in the ion trap. The positioning ability is an enabling technology for trap-integration as it allows for complete freedom in the alignment of the trapped atom with respect to the integrated element. In the second part, the construction of the experimental setup and the integrated "fibertrap" is described. In our experiment, a single 38Sr+ is trapped 670 [mu]m above the end of an optical fiber in a cryogenic (8 K) surface-electrode ion trap. The fiber serves as an integrated source of laser light, which drives the quadrupole qubit transition of 88Sr+. Using in situ translation of the ion, the Gaussian beam profile of the fiber output is imaged, and the fiberion displacement, in units of the mode waist at the ion, is optimized to within 0.13 ± 0.10 of the mode center despite an initial offset of 3.30 ± 0.10 arising from fabrication. We also quantify the perturbative effects of the fiber dielectric on ion trap operation. Light-induced charging by 125 [mu]W of 674 nm fiber light is measured as an induced electric field of ~ 10 V/m at the ion, with charging and discharging time constants of 1.6 ± 0.3 s and 4.7 t 0.6 s. These measurements are of general importance to trapped-ion quantum computing, where the scalability of the platform depends crucially on the feasibility of on-chip optics integration.

Author : Stephan Schulz
Publisher : Lulu.com
Page : 192 pages
File Size : 10,12 MB
Release : 2010-09-13
Category : Science
ISBN : 0557621852

GET BOOK

The development of scalable microfabricated ion traps with multiple segments for the realization of quantum computing is a challenging task in quantum information science. The research on the design, development, fabrication, and operation of the first European micro-trap is shown in this thesis. This chip-based micro-trap is an outstanding candidate towards experiments for a future quantum processor with trapped single ions. In the experiments coherent quantum state manipulation is demonstrated, and sideband cooling to the motional ground state is realized. The heating rate is determined and the applicability for quantum computation is proven. Furthermore planar trap designs are investigated - a planar microparticle trap was built and operated. A linear microfabricated planar trap was operated, showing the proof of concept of a novel designed and fabricated Y-shaped planar trap.

Author : Robert A. Meyers
Publisher : Springer
Page : 0 pages
File Size : 22,87 MB
Release : 2011-10-19
Category : Computers
ISBN : 9781461417996

GET BOOK

Complex systems are systems that comprise many interacting parts with the ability to generate a new quality of collective behavior through self-organization, e.g. the spontaneous formation of temporal, spatial or functional structures. These systems are often characterized by extreme sensitivity to initial conditions as well as emergent behavior that are not readily predictable or even completely deterministic. The recognition that the collective behavior of the whole system cannot be simply inferred from an understanding of the behavior of the individual components has led to the development of numerous sophisticated new computational and modeling tools with applications to a wide range of scientific, engineering, and societal phenomena. Computational Complexity: Theory, Techniques and Applications presents a detailed and integrated view of the theoretical basis, computational methods, and state-of-the-art approaches to investigating and modeling of inherently difficult problems whose solution requires extensive resources approaching the practical limits of present-day computer systems. This comprehensive and authoritative reference examines key components of computational complexity, including cellular automata, graph theory, data mining, granular computing, soft computing, wavelets, and more.

Author : Danielius Kramnik
Publisher :
Page : 164 pages
File Size : 11,96 MB
Release : 2020
Category :
ISBN :

GET BOOK

Quantum information processing (QIP) has emerged as a powerful new computing paradigm as traditional Moore’s law scaling slows due to skyrocketing costs of shrinking feature sizes, interconnects becoming the dominant source of energy consumption and delay as transistor critical dimensions fall below 10 nm, and power density limiting the activity factor in digital systems on a chip. Quantum computers use quantum states (“qubits”) to store and manipulate information, giving them fundamental performance advantages over classical digital computers in certain applications. Although the feasibility of QIP has been proven for decades using smallscale (. 50 physical qubit) demonstration systems, the main problem is achieving scalability using existing designs. Individual atomic ions trapped by electromagnetic fields in a vacuum and manipulated using lasers have been a leading candidate for a physical substrate for QIP since the beginning, but scaling has been limited by the bulky free-space optics that are traditionally used for state manipulation and readout. CMOS chips with integrated photonics, on the other hand, can solve the scalability issue by tightly packing photodetectors for state readout, classical computing resources for timing and control, and optical waveguides and modulators for state manipulation onto the same chip. In recent years researchers have fabricated a planar ion trap in a CMOS foundry and addressed individual ions using photonic components built on a custom-fabricated ion trap, but the problem of CMOS-integrated state readout remains unaddressed. Current approaches to state readout use a large external lens and photomultiplier tube to detect state-dependent ion fluorescence. Instead, fabricating silicon photodetectors directly below the trap location would eliminate large light collection optics and enable scaling of readout to greater numbers of ions by closing the sensing-to-manipulation loop on-chip. This thesis addresses this issue by developing hardware and methodology to perform detailed characterization of single-photon avalanche diodes (SPADs) integrated on a CMOS ion trap at cryogenic temperatures, showing that state readout with speed and fidelity comparable to the bulk optics approach is possible. Based on our results, state readout experiments using a CMOS ion trap with integrated SPADs are presently underway at the MIT Lincoln Laboratory.

Author : National Academies of Sciences, Engineering, and Medicine
Publisher : National Academies Press
Page : 315 pages
File Size : 13,61 MB
Release : 2020-09-14
Category : Science
ISBN : 0309499542

GET BOOK

The field of atomic, molecular, and optical (AMO) science underpins many technologies and continues to progress at an exciting pace for both scientific discoveries and technological innovations. AMO physics studies the fundamental building blocks of functioning matter to help advance the understanding of the universe. It is a foundational discipline within the physical sciences, relating to atoms and their constituents, to molecules, and to light at the quantum level. AMO physics combines fundamental research with practical application, coupling fundamental scientific discovery to rapidly evolving technological advances, innovation and commercialization. Due to the wide-reaching intellectual, societal, and economical impact of AMO, it is important to review recent advances and future opportunities in AMO physics. Manipulating Quantum Systems: An Assessment of Atomic, Molecular, and Optical Physics in the United States assesses opportunities in AMO science and technology over the coming decade. Key topics in this report include tools made of light; emerging phenomena from few- to many-body systems; the foundations of quantum information science and technologies; quantum dynamics in the time and frequency domains; precision and the nature of the universe, and the broader impact of AMO science.

Author : Karan Kartik Mehta
Publisher :
Page : 183 pages
File Size : 50,22 MB
Release : 2017
Category :
ISBN :

GET BOOK

Individual atomic ions confined in designed electromagnetic potentials and manipulated via lasers are strong candidates as physical bases for quantum information processing (QIP). This is in large part due to their long coherence times, in distinguishability, and strong Coulomb interactions. Much work in recent years has utilized these properties to implement increasingly precise quantum operations essential for QIP, as well as to conduct increasingly sophisticated experiments on few-ion systems. Many questions remain however regarding how to implement the significant classical apparatus required to control and measure many ions (and indeed any physical qubit under study) in a scalable way that furthermore does not compromise qubit quality. This work draws on techniques in integrated optics to address this question. Planar-fabricated waveguides and gratings integrated with planar ion traps are demonstrated to allow optical addressing of individual 88Sr+ions 50 [mu]m above the chip surface with distraction-limited focused beams, with advantages in stability and scalability. Motivated by the requirement for low crosstalk in qubit addressing, we show also that intuitively designed devices can generate precisely tailored intensity profiles at the ion locations, with distraction-limited side lobe intensities characterized to the 5x10-6 level in relative intensity up to 25 [mu]m from the focus. Such devices can be implemented alongside complex systems in complementary metal-oxide-semiconductor (CMOS) processes. We show in addition that the multiple patternable metal layers present in CMOS processes can be used to create complex planar ion traps with performance comparable to simple single-layer traps, and that CMOS silicon avalanche photodiodes may be employed for scalable quantum state readout. Finally we show initial results on integrated electro-optic modulators for visible light. These results open possibilities for experiments with trapped ions in the short term, and indicate routes to achieving large-scale systems of thousands or more ions in the future. Though ion qubits may seem isolated from scalable solid-state technologies, it appears this apparent isolation may uniquely allow a cooperation with complex planar-fabricated optical and electronic systems without introducing additional decoherence.

Author : Marko Cetina (Ph. D.)
Publisher :
Page : 250 pages
File Size : 50,31 MB
Release : 2011
Category :
ISBN :

GET BOOK

This thesis presents two hybrid systems for quantum information processing - one joining cold ions and cold atoms and another coupling linear chains of atomic ions with photons via an optical resonator. The first experimental realization of a hybrid cold-ion / cold-atom system is presented in the form of Yb atoms trapped in a magneto-optical trap overlapped with Yb+ ions stored in a radio-frequency (RF) planar Paul trap. The overlap between the excited MOT atoms and the ion trap is used to obtain isotope-selective ion trap loading rates 104 times higher than previously achieved. The interaction between atoms and ions is measured by observing near-resonant charge-exchange collisions between Yb and Yb+ with a collision rate matching the classical Langevin cross-section. Momentum transfer between cold atoms and cold ions is observed via collisions of Yb+ ions with laser-cooled Rb atoms and a classical limit to the ion-atom collision energy in RF traps derived, with relevance to current ion experiments. The second part of the thesis presents the first integration of a scalable, microfabricated surface ion trap chip with an optical resonator. This chip trap is used to produce a linear array of ion traps and load these traps with isotopically-selected chains of Yb+ ions. The ion chains are overlapped with the mode of an optical resonator and the coupling of the individual ions to the resonator mode demonstrated by recording the frequency spectrum of the ions' near-resonance fluorescence. These measurements demonstrate the capability of the present system to store and process quantum information stored in short ion chains and to communicate this information via photons, with applications to large-scale trapped ion quantum information processing. The strong-near resonant optical field available inside the optical resonator may also be used to produce a periodic optical potential for trapped ions, with applications to quantum simulation.

Author : Henry O. Everitt
Publisher : Springer Science & Business Media
Page : 303 pages
File Size : 14,30 MB
Release : 2007-04-03
Category : Science
ISBN : 0387277323

GET BOOK

Practical quantum computing still seems more than a decade away, and researchers have not even identified what the best physical implementation of a quantum bit will be. There is a real need in the scientific literature for a dialogue on the topic of lessons learned and looming roadblocks. This reprint from Quantum Information Processing is dedicated to the experimental aspects of quantum computing and includes articles that 1) highlight the lessons learned over the last 10 years, and 2) outline the challenges over the next 10 years. The special issue includes a series of invited articles that discuss the most promising physical implementations of quantum computing. The invited articles were to draw grand conclusions about the past and speculate about the future, not just report results from the present.