Atom interferometric sensors and quantum information processors must maintain coherence while the evolving quantum wavefunction is split, transformed and recombined, but suffer from experimental inhomogeneities and uncertainties in the speeds and paths of these operations. Several error-correction techniques have been proposed to isolate the variable of interest. Here we apply composite pulse methods to velocity-sensitive Raman state manipulation in a freely-expanding thermal atom cloud. We compare several established pulse sequences, and follow the state evolution within them. The agreement between measurements and simple predictions shows the underlying coherence of the atom ensemble, and the inversion infidelity in an 80 micro-Kelvin atom cloud is halved. Composite pulse techniques, especially if tailored for atom interferometric applications, should allow greater interferometer areas, larger atomic samples and longer interaction times, and hence improve the sensitivity of quantum technologies from inertial sensing and clocks to quantum information processors and tests of fundamental physics

Deep learning (DL) techniques are gaining more and more attention in the software engineering community. They have been used to support several code-related tasks, such as automatic bug fixing and code comments generation. Recent studies in the Natural Language Processing (NLP) field have shown that the Text-To-Text Transfer Transformer (T5) architecture can achieve state-of-the-art performance for a variety of NLP tasks. The basic idea behind T5 is to first pre-train a model on a large and generic dataset using a self-supervised task (e.g., filling masked words in sentences). Once the model is pre-trained, it is fine-tuned on smaller and specialized datasets, each one related to a specific task (e.g., language translation, sentence classification). In this paper, we empirically investigate how the T5 model performs when pre-trained and fine-tuned to support code-related tasks. We pre-train a T5 model on a dataset composed of natural language English text and source code. Then, we fine-tune such a model by reusing datasets used in four previous works that used DL techniques to: (i) fix bugs, (ii) inject code mutants, (iii) generate assert statements, and (iv) generate code comments. We compared the performance of this single model with the results reported in the four original papers proposing DL-based solutions for those four tasks. We show that our T5 model, exploiting additional data for the self-supervised pre-training phase, can achieve performance improvements over the four baselines.

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Physical Chemistry Chemical Physics (PCCP) is a high quality journal with a large international readership from many communitiesOnly very important, insightful and high-quality work should be recommended for publication in PCCP.To be accepted in PCCP -a manuscript must report: Very high quality, reproducible new work  Important new physical insights of significant general interest  A novel, stand-alone contribution Routine or incremental work should not be recommended for publication. Purely synthetic work is not suitable for PCCPIf you rate the article as 'routine' yet recommend acceptance, please give specific reasons in your report.Less than 50% of articles sent for peer review are recommended for publication in PCCP. The current PCCP Impact Factor is 4.20.PCCP is proud to be a leading journal. We thank you very much for your help in evaluating this manuscript. Your advice as a referee is greatly appreciated.With our best wishes, Anna Simpson (pccp@rsc.org) Prof Daniella Goldfarb Managing Editor, PCCP Chair, PCCP Editorial Board General Guidance (For further details, see the RSC's Refereeing Procedure and Policy)Referees have the responsibility to treat the manuscript as confidential. Please be aware of our Ethical Guidelines which contain full information on the responsibilities of referees and authors. When preparing your report, please:• Comment on the originality, importance, impact and scientific reliability of the work;• State clearly whether you would like to see the paper accepted or rejected and give detailed comments (with references) that will both help the Editor to make a decision on the paper and the authors to improve it; Please inform the Editor if:• There is a conflict of interest;• There is a significant part of the work which you cannot referee with confidence;• If the work, or a significant part of the work, has previously been published, including online publication, or if the work represents part of an unduly fragmented investigation. When submitting your report, please:• Provide your report rapidly and within the specified deadline, or inform the Editor immediately if you cannot do so. We welcome suggestions of alternative referees. The Stern-Gerlach experiment is a seminal experiment in quantum physics, involving the interaction between a particle with spin and an applied magnetic field gradient. A recent article [Wennerström et al., Phys. Chem. Chem. Phys., 2012, 14, 1677-1684 claimed that a full understanding of the Stern-Gerlach experiment can only be attained if transverse spin relaxation is taken into account, generated by fluctuating magnetic fields originating in the magnetic materials which generate the field gradient. This interpretation is contrary to the standard quantum description of the Stern-Gerlach experiment, which requires no dissipative effects. We present simulations of conventional quantum dynamics in the Stern-Gerlach experiment, using extended Wigner functions to describe the propagation of the quantum state in space and time. No relaxation effects are require...

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Excited low-spin states in 96 Mo and 98 Mo have been studied in γγ angular correlation experiments in order to determine spins and multipole mixing ratios. Furthermore, from a Doppler lineshape analysis effective lifetimes τ in the femtosecond range were obtained. The experimental data show a complex spectrum due to configuration mixing, which is confirmed by Interacting Boson Model calculations based on a Skyrme energy density functional. The M 1-transition strengths of transitions depopulating excited 2 + states to the first 2 + state are discussed in terms of the proton-neutron mixed symmetry.

The exact nature of the lowest K π =2 + rotational bands in all deformed nuclei remains obscure. Traditionally they are assumed to be collective vibrations of the nuclear shape in the γ degree of freedom perpendicular to the nuclear symmetry axis. Very few such γ-bands have been traced past the usual back-bending rotational alignments of high-j nucleons. We have investigated the structure of positive-parity bands in the N=90 nucleus 156 Dy, using the 148 Nd(

Screen recordings of mobile applications are easy to obtain and capture a wealth of information pertinent to software developers (e.g., bugs or feature requests), making them a popular mechanism for crowdsourced app feedback. Thus, these videos are becoming a common artifact that developers must manage. In light of unique mobile development constraints, including swift release cycles and rapidly evolving platforms, automated techniques for analyzing all types of rich software artifacts provide benet to mobile developers. Unfortunately, automatically analyzing screen recordings presents serious challenges, due to their graphical nature, compared to other types of (textual) artifacts. To address these challenges, this paper introduces V2S, a lightweight, automated approach for translating video recordings of Android app usages into replayable scenarios. V2S is based primarily on computer vision techniques and adapts recent solutions for object detection and image classication to detect and classify user actions captured in a video, and convert these into a replayable test scenario. We performed an extensive evaluation of V2S involving 175 videos depicting 3,534 GUI-based actions collected from users exercising features and reproducing bugs from over 80 popular Android apps. Our results illustrate that V2S can accurately replay scenarios from screen recordings, and is capable of reproducing ⇡ 89% of our collected videos with minimal overhead. A case study with three industrial partners illustrates the potential usefulness of V2S from the viewpoint of developers. CCS CONCEPTS • Software and its engineering → Software maintenance tools; Software verication and validation; Application specic development environments.