Ion trap transducers for quantum electromechanical oscillators

An enduring challenge for contemporary physics is to experimentally observe and control quantum behavior in macroscopic systems. We show that a single trapped atomic ion could be used to probe the quantum nature of a mesoscopic mechanical oscillator precooled to 4K, and furthermore, to cool the oscillator with high efficiency to its quantum ground state. The proposed experiment could be performed using currently available technology.Comment: 4 pages, 2 figure

Scaling and Suppression of Anomalous Heating in Ion Traps

We measure and characterize anomalous motional heating of an atomic ion confined in the lowest quantum levels of a novel rf ion trap that features moveable electrodes. The scaling of heating with electrode proximity is measured, and when the electrodes are cooled from 300 to 150 K, the heating rate is suppressed by an order of magnitude. This provides direct evidence that anomalous motional heating of trapped ions stems from microscopic noisy potentials on the electrodes that are thermally driven. These observations are relevant to decoherence in quantum information processing schemes based on trapped ions and perhaps other charge-based quantum systems

Business in Nebraska # 278 - November 1967

The Nebraska Department of Economic Development (James W. Monroe) After 100 years of growth and prosperity based firmly upon a nearly self-sufficient agricultural economy, why has Nebraska seen fit to depart from its rural image and increase its efforts in the highly competitive business of attracting industry? Business Summary (E. L. Burgess) August\u27s dollar volume of business in Nebraska increased 3.3% from August, 1966 and the physical volume increased 2.7%. The U.S. dollar volume rose 5.3% from August, 1966. The U.S. construction activity index increased over year-ago levels for the first time since May, 1966. Nebraska\u27s construction index, having last shown an increase over year-ago levels in September, 1966, remained down with a 14.3% decline from August, 1966. Life insurance sales (-1.1%) was the only other Nebraska indicator declining from year-ago levels. Review (E. S. Wallace

Coherent Error Suppression in Multi-Qubit Entangling Gates

We demonstrate a simple pulse shaping technique designed to improve the fidelity of spin-dependent force operations commonly used to implement entangling gates in trapped-ion systems. This extension of the M{\o}lmer-S{\o}rensen gate can theoretically suppress the effects of certain frequency and timing errors to any desired order and is demonstrated through Walsh modulation of a two-qubit entangling gate on trapped atomic ions. The technique is applicable to any system of qubits coupled through collective harmonic oscillator modes

Librarians as Partners: Moving from Research Supporters to Research Partners

Academic libraries have long been discussing the need to remain relevant and demonstrate value to their institutions. This paper explores how academic libraries can expand the concept of embedded librarianship to create research partnerships at universities. Such partnerships will enhance value to the institutional research output, as well as increase the visibility of unique librarian skills and library resources. Using a case study from a public research I university, the author discusses innovative roles for librarians on research teams. Embedding academic librarians fully into the research enterprise recognizes the significant contributions that librarians can make as research partners.National Institute on Disability and Rehabilitation Researc

Decoherence in ion traps due to laser intensity and phase fluctuations

We consider one source of decoherence for a single trapped ion due to intensity and phase fluctuations in the exciting laser pulses. For simplicity we assume that the stochastic processes involved are white noise processes, which enables us to give a simple master equation description of this source of decoherence. This master equation is averaged over the noise, and is sufficient to describe the results of experiments that probe the oscillations in the electronic populations as energy is exchanged between the internal and electronic motion. Our results are in good qualitative agreement with recent experiments and predict that the decoherence rate will depend on vibrational quantum number in different ways depending on which vibrational excitation sideband is used.Comment: 2 figures, submitted to PR

Characteristics of severe life events, attachment style, and depression – Using a new online approach

Objectives Severe life events are established as provoking agents for depression in combination with vulnerability factors. Identifying features of severe events improves the prediction of disorder but are rarely utilized, mainly because life event research is increasingly dominated by self‐report checklists with no capacity for inferring such characteristics. This paper investigates the association of severe life events’ features with depression and insecure attachment styles using a new online measure of life events in a clinical and control sample. Methods A total of 202 participants (75 clinical and 127 matched control participants), taken from an earlier national Depression Case Control genetic study and followed up after 12 years, completed the Computerised Life Events Assessment Record to assess characteristics of life events, the Vulnerable Attachment Style Questionnaire to measure attachment insecurity, and the General Health Questionnaire to measure depression. Results The clinical group had higher self‐reported depression, severe life events, and insecure attachment style. They also reported more loss, danger, humiliation, and trauma severe events. Intra‐respondent analysis showed individuals experiencing these types of events were more likely to report depression. Insecure attachment style and severe life events were both significantly related to recent depression and history of depressive disorder. Anxious attachment style was significantly related to relationship events and bereavements, as well as severe loss or humiliation events, whereas avoidant style was not. Conclusions Identifying salient features of severe life events improves associations with depression and insecure attachment style. Utilizing a new online approach can aid research and clinical approaches for depression at low cost. Practitioner points Salient features of severe life events (e.g., loss, humiliation) give insight into the potential impact on attachment vulnerability and depression. Clinicians and researchers can use online methods to economically gain detailed life event information needed for clinical formulation and valid data on stressors. The self‐reported scale for recent depression is only a proxy measure of clinical disorder, but the clinical group selection is a more robust criterion for depression history

Preparing encoded states in an oscillator

Recently a scheme has been proposed for constructing quantum error-correcting codes that embed a finite-dimensional code space in the infinite-dimensional Hilbert space of a system described by continuous quantum variables. One of the difficult steps in this scheme is the preparation of the encoded states. We show how these states can be generated by coupling a continuous quantum variable to a single qubit. An ion trap quantum computer provides a natural setting for a continuous system coupled to a qubit. We discuss how encoded states may be generated in an ion trap.Comment: 5 pages, 4 figures, RevTe

Entanglement of Atomic Qubits using an Optical Frequency Comb

We demonstrate the use of an optical frequency comb to coherently control and entangle atomic qubits. A train of off-resonant ultrafast laser pulses is used to efficiently and coherently transfer population between electronic and vibrational states of trapped atomic ions and implement an entangling quantum logic gate with high fidelity. This technique can be extended to the high field regime where operations can be performed faster than the trap frequency. This general approach can be applied to more complex quantum systems, such as large collections of interacting atoms or molecules.Comment: 4 pages, 5 figure