1,675 research outputs found
Quantum control of the motional states of trapped ions through fast switching of trapping potentials
We propose a new scheme for supplying voltages to the electrodes of
microfabricated ion traps, enabling access to a regime in which changes to the
trapping potential are made on timescales much shorter than the period of the
secular oscillation frequencies of the trapped ions. This opens up
possibilities for speeding up the transport of ions in segmented ion traps and
also provides access to control of multiple ions in a string faster than the
Coulomb interaction between them. We perform a theoretical study of ion
transport using these methods in a surface-electrode trap, characterizing the
precision required for a number of important control parameters. We also
consider the possibilities and limitations for generating motional state
squeezing using these techniques, which could be used as a basis for
investigations of Gaussian-state entanglement.Comment: Accepted by New Journal of Physic
A proposal for a scalable universal bosonic simulator using individually trapped ions
We describe a possible architecture to implement a universal bosonic
simulator (UBS) using trapped ions. Single ions are confined in individual
traps, and their motional states represent the bosonic modes. Single-mode
linear operators, nonlinear phase-shifts, and linear beam splitters can be
realized by precisely controlling the trapping potentials. All the processes in
a bosonic simulation, except the initialization and the readout, can be
conducted beyond the Lamb-Dicke regime. Aspects of our proposal can also be
applied to split adiabatically a pair of ions in a single trap
Adult Social Work and High Risk Domestic Violence Cases
Summary
This article focuses on adult social work’s response in England to high-risk domestic violence cases and the role of adult social workers in Multi-Agency Risk and Assessment Conferences. (MARACs). The research was undertaken between 2013-2014 and
focused on one city in England and involved the research team attending MARACs, Interviews with 20 adult social workers, 24 MARAC attendees, 14 adult service users at time T1 (including follow up interviews after six months, T2), focus groups with IDVAs and Women’s Aid and an interview with a Women’s Aid service user.
Findings
The findings suggest that although adult social workers accept the need to be involved in domestic violence cases they are uncertain of what their role is and are confused with the need to operate a parallel domestic violence and adult safeguarding approach, which is further, complicated by issues of mental capacity. MARACS are identified as overburdened, under-represented meetings staffed by committed managers. However, they are in danger of becoming managerial processes neglecting the service users they are meant to protect.
Applications
The article argues for a re-engagement of adult social workers with domestic violence that has increasingly become over identified with child protection. It also raises the issue whether MARACS remain fit for purpose and whether they still represent the best possible response to multi-agency coordination and practice in domestic violence
A diode laser stabilization scheme for 40Ca+ single ion spectroscopy
We present a scheme for stabilizing multiple lasers at wavelengths between
795 and 866 nm to the same atomic reference line. A reference laser at 852 nm
is stabilized to the Cs D2 line using a Doppler-free frequency modulation
technique. Through transfer cavities, four lasers are stabilized to the
relevant atomic transitions in 40Ca+. The rms linewidth of a transfer-locked
laser is measured to be 123 kHz with respect to an independent atomic
reference, the Rb D1 line. This stability is confirmed by the comparison of an
excitation spectrum of a single 40Ca+ ion to an eight-level Bloch equation
model. The measured Allan variance of 10^(-22) at 10 s demonstrates a high
degree of stability for time scales up to 100 s.Comment: 8 pages, 11 figure
An ion trap built with photonic crystal fibre technology
We demonstrate a surface-electrode ion trap fabricated using techniques
transferred from the manufacture of photonic-crystal fibres. This provides a
relatively straightforward route for realizing traps with an electrode
structure on the 100 micron scale with high optical access. We demonstrate the
basic functionality of the trap by cooling a single ion to the quantum ground
state, allowing us to measure a heating rate from the ground state of 787(24)
quanta/s. Variation of the fabrication procedure used here may provide access
to traps in this geometry with trap scales between 100 um and 10 um.Comment: 6 pages, 4 figure
WHIPLASH: The possible impact of context on diagnosis
This study explores the importance of context when diagnosing Whiplash Associated Disorders (WAD). Whiplash is a complex injury and there is considerable variation in its diagnosis and treatment. Research has focussed on RTAs, whilst there is a paucity of evidence relating to WAD in sport. It is unclear whether WAD is simply not occurring in sport, or if such injuries are occurring but are not identified as WAD. In the current study, 87 postgraduate physiotherapists were asked to classify an injury reported in a short vignette. Two parallel vignettes were used, which were identical except for the context of the injury (one being an RTA and the other being within sport). Each participant responded to only one of these. It was found that, even within a sample of experienced physiotherapists, the injury environment impacted on diagnosis, despite the symptoms being identical. A significantly higher proportion of therapists diagnosed WAD within the RTA context than within the sporting context. Additionally, there were differences between the two context groups in relation to the diagnostic terminology used by participants. Most respondents had heard of the CSP whiplash guidelines but only a minority had actively used these. The majority of respondents were also aware of the litigation aspects of RTAs
- …