Bothered bloggings and troubled tweets: constructions of stress and concerns for early-career academics

While recent studies suggest that stress is becoming more prominent for academics, very little research has been conducted on understanding the realities of stress for early-career academics. Through the employment of social constructionist epistemology and theory as a framework for research, our study examines how early-career academics language and construct experiences of stress and concern. We employed a constructionist thematic analysis. This involved selecting a sample of blogs and Twitter microblogs to code and identifying important themes, in relation to stress and concern. Through a preliminary analysis of blogs, we found that there were recurring concerns on work-life balance, a competitive culture that eroded collegiality and social support, and there were worries about the insecurity of work. Our analysis of Twitter tweets found a range of concerns. There were issues of health and wellbeing, being unfairly discriminated against and not recognised by senior academic staff, structural barriers in the application and access of research, publishing issues and advice in relation to accessibility of research outputs, a governmentality on the standards of academic conduct, and concerns on flexibility in relation to time and work life balance. The findings have implications for higher education institutions in the support and career development of early career academics

A solid state spin-wave quantum memory for time-bin qubits

We demonstrate the first solid-state spin-wave optical quantum memory with on-demand read-out. Using the full atomic frequency comb scheme in a \PrYSO crystal, we store weak coherent pulses at the single-photon level with a signal to noise ratio $> 10$. Narrow-band spectral filtering based on spectral hole burning in a second \PrYSO crystal is used to filter out the excess noise created by control pulses to reach an unconditional noise level of $(2.0 \pm 0.3) \times10^{-3}$ photons per pulse. We also report spin-wave storage of photonic time-bin qubits with conditional fidelities higher than a measure and prepare strategy, demonstrating that the spin-wave memory operates in the quantum regime. This makes our device the first demonstration of a quantum memory for time-bin qubits, with on demand read-out of the stored quantum information. These results represent an important step for the use of solid-state quantum memories in scalable quantum networks.Comment: 10 pages, 10 figure

Photon echo without a free induction decay in a double-Lambda system

We have characterized a novel photon-echo pulse sequence for a double-$\Lambda$ type energy level system where the input and rephasing transitions are different to the applied $\pi$-pulses. We show that despite having imperfect $\pi$-pulses (associated with large coherent emission due to free induction decay), the noise added is only 0.019$\pm$0.001 relative to the shot noise in the spectral mode of the echo. Using this echo pulse sequence in the `rephased amplified spontaneous emission' (RASE) scheme \cite{Ledingham2010} will allow for generation of entangled photon pairs that are in different frequency, temporal, and potentially spatial modes to any bright driving fields. The coherence and efficiency properties of this sequence were characterized in a Pr:YSO crystal

Coherent Storage of Temporally Multimode Light Using a Spin-Wave Atomic Frequency Comb Memory

We report on coherent and multi-temporal mode storage of light using the full atomic frequency comb memory scheme. The scheme involves the transfer of optical atomic excitations in Pr3+:Y2SiO5 to spin-waves in the hyperfine levels using strong single-frequency transfer pulses. Using this scheme, a total of 5 temporal modes are stored and recalled on-demand from the memory. The coherence of the storage and retrieval is characterized using a time-bin interference measurement resulting in visibilities higher than 80%, independent of the storage time. This coherent and multimode spin-wave memory is promising as a quantum memory for light.Comment: 17 pages, 5 figure

Towards Laser Driven Hadron Cancer Radiotherapy: A Review of Progress

It has been known for about sixty years that proton and heavy ion therapy is a very powerful radiation procedure for treating tumours. It has an innate ability to irradiate tumours with greater doses and spatial selectivity compared with electron and photon therapy and hence is a tissue sparing procedure. For more than twenty years powerful lasers have generated high energy beams of protons and heavy ions and hence it has been frequently speculated that lasers could be used as an alternative to RF accelerators to produce the particle beams necessary for cancer therapy. The present paper reviews the progress made towards laser driven hadron cancer therapy and what has still to be accomplished to realise its inherent enormous potential.Comment: 40 pages, 24 figure

Non-classical photon streams using rephased amplified spontaneous emission

We present a fully quantum mechanical treatment of optically rephased photon echoes. These echoes exhibit noise due to amplified spontaneous emission, however this noise can be seen as a consequence of the entanglement between the atoms and the output light. With a rephasing pulse one can get an "echo" of the amplified spontaneous emission, leading to light with nonclassical correlations at points separated in time, which is of interest in the context of building wide bandwidth quantum repeaters. We also suggest a wideband version of DLCZ protocol based on the same ideas.Comment: 5 pages, 4 figures. Added section

Storage of up-converted telecom photons in a doped crystal

We report on an experiment that demonstrates the frequency up-conversion of telecommunication wavelength single-photon-level pulses to be resonant with a $\mathrm{Pr}^{3+}$:$\mathrm{Y}_2\mathrm{Si}\mathrm{O}_5$ crystal. We convert the telecom photons at $1570\,\mathrm{nm}$ to $606\,\mathrm{nm}$ using a periodically-poled potassium titanyl phosphate nonlinear waveguide. The maximum device efficiency (which includes all optical loss) is inferred to be $\eta_{\mathrm{dev}}^{\mathrm{max}} = 22 \pm 1\,$ (internal efficiency $\eta_{\mathrm{int}} = 75\pm8\,$) with a signal to noise ratio exceeding 1 for single-photon-level pulses with durations of up to 560$\,$ns. The converted light is then stored in the crystal using the atomic frequency comb scheme with storage and retrieval efficiencies exceeding $\eta_{\mathrm{AFC}} = 20\,$ for predetermined storage times of up to $5\,\mu\mathrm{s}$. The retrieved light is time delayed from the noisy conversion process allowing us to measure a signal to noise ratio exceeding 100 with telecom single-photon-level inputs. These results represent the first demonstration of single-photon-level optical storage interfaced with frequency up-conversion

Photon echo quantum memories in inhomogeneously broadened two level atoms

Here we propose a solid-state quantum memory that does not require spectral holeburning, instead using strong rephasing pulses like traditional photon echo techniques. The memory uses external broadening fields to reduce the optical depth and so switch off the collective atom-light interaction when desired. The proposed memory should allow operation with reasonable efficiency in a much broader range of material systems, for instance Er3+ doped crystals which have a transition at 1.5 um. We present analytic theory supported by numerical calculations and initial experiments.Comment: 7 pages, 8 figure

Data quality predicts care quality: findings from a national clinical audit

Background: Missing clinical outcome data are a common occurrence in longitudinal studies. Data quality in clinical audit is a particular cause for concern. The relationship between departmental levels of missing clinical outcome data and care quality is not known. We hypothesise that completeness of key outcome data in a national audit predicts departmental performance. Methods: The National Clinical Audit for Rheumatoid and Early Inflammatory Arthritis (NCAREIA) collected data on care of patients with suspected rheumatoid arthritis (RA) from early 2014 to late 2015. This observational cohort study collected data on patient demographics, departmental variables, service quality measures including time to treatment, and the key RA clinical outcome measure, disease activity at baseline, and 3 months follow-up. A mixed effects model was conducted to identify departments with high/low proportions of missing baseline disease activity data with the results plotted on a caterpillar graph. A mixed effects model was conducted to assess if missing baseline disease activity predicted prompt treatment. Results: Six thousand two hundred five patients with complete treatment time data and a diagnosis of RA were recruited from 136 departments. 34.3% had missing disease activity at baseline. Mixed effects modelling identified 13 departments with high levels of missing disease activity, with a cluster observed in the Northwest of England. Missing baseline disease activity was associated with not commencing treatment promptly in an adjusted mix effects model, odds ratio 0.50 (95% CI 0.41 to 0.61, p < 0.0001). Conclusions: We have shown that poor engagement in a national audit program correlates with the quality of care provided. Our findings support the use of data completeness as an additional service quality indicator