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Compact, high power lasers with narrow linewidth are important tools for the manipulation of quantum systems. We demonstrate a compact, self-injection locked, Fabry-Perot semiconductor laser diode with high output power at 493 nm. A high quality factor magnesium fluoride whispering gallery mode resonator enables both high passive stability and 1 kHz instantaneous linewidth. We use this laser for laser-cooling, in-situ isotope purifcation, and probing barium atomic ions confined in a radio-frequency ion trap. The results here demonstrate the suitability of these lasers in trapped ion quantum information processing and for probing weak coherent optical transitions.

AbstractThe recently demonstrated trapping and laser cooling of 133Ba+ has opened the door to the use of this nearly ideal atom for quantum information processing. However, before high-fidelity qubit operations can be performed, a number of unknown state energies are needed. Here, we report measurements of the 2P3/2 and 2D5/2 hyperfine splittings, as well as the 2P3/2 ↔ 2S1/2 and 2P3/2 ↔ 2D5/2 transition frequencies. Using these transitions, we demonstrate high-fidelity 133Ba+ hyperfine qubit manipulation with electron shelving detection to benchmark qubit state preparation and measurement (SPAM). Using single-shot, threshold discrimination, we measure an average SPAM fidelity of $${\mathcal{F}}=0.99971(3)$$ F = 0.99971 ( 3 ) , a factor of ≈2 improvement over the best reported performance of any qubit.

Ensemble music performance requires musicians to achieve precise interpersonal coordination while maintaining autonomous control over their own actions. To do so, musicians dynamically shift between integrating other performers' actions into their own action plans and maintaining a distinction between their own and others' actions. Research in laboratory settings has shown that this dynamic process of self-other integration and distinction is indexed by sensorimotor alpha oscillations. The purpose of the current descriptive case study was to examine oscillations related to self-other integration and distinction in a naturalistic performance context. We measured alpha activity from four violinists during a concert hall performance of a 60-musician orchestra. We selected a musical piece from the orchestra's repertoire and, before analyzing alpha activity, performed a score analysis to divide the piece into sections that were expected to strongly promote self-other integration and distinction. In line with previous laboratory findings, performers showed suppressed and enhanced alpha activity during musical sections that promoted self-other integration and distinction, respectively. The current study thus provides preliminary evidence that findings from carefully controlled laboratory experiments generalize to complex real-world performance. Its findings also suggest directions for future research and potential applications of interest to musicians, music educators, and music therapists. [ABSTRACT FROM AUTHOR]

For older adults living with mild cognitive impairment or dementia, creative arts-based activities can offer many benefits from enjoyment as leisure/recreation to an avenue to maintain cognitive, social and emotional wellbeing. With growing interest and recognition that technology could have potential to assist in delivering these activities in more accessible and personalised ways, a scoping review was undertaken to systematically examine the scientific literature for technology-assisted creative arts activities for older adults living with dementia. We searched PubMed, PsychINFO, Web of Science, Scopus and ACM Digital Library databases using keywords centering on population with dementia, an intervention using technology, and a context of creative arts, with no restrictions on the type of outcome measured. We retrieved 3739 records, with an additional 22 from hand-searching. 51 full-text articles met the inclusion and exclusion criteria. Findings of the review indicate technologies principally being designed for music activities (listening, and music-making), as well as storytelling and visual arts. The majority of devices were custom-made, with studies mainly reporting on validating the success of the device/intervention. This suggests most work in the field is currently at prototyping stage, although a few devices are now commercially available. Recommendations for future research includes involvement of participants reporting on their previous experiences in the arts and how this influences co-design choices, and inclusion of different severities of dementia in the participant/co-design group. Furthering device development past prototyping stage as well as collaboration between teams would enable comparisons to be made across different types of devices used for the same activity, and comparisons across arts-based activities that could lead to cross-disciplinary outcomes for the design of creative arts-based assistive technologies. [ABSTRACT FROM AUTHOR]

Compact cold-atom sensors depend on vacuum technology. One of the major limitations to miniaturizing these sensors is the active pumps--typically ion pumps--that are required to sustain the low pressure needed for laser cooling. Although passively pumped chambers have been proposed as a solution to this problem, technical challenges have prevented successful operation at the levels needed for cold-atom experiments. The authors present the first demonstration of a vacuum package successfully independent of ion pumps for more than a week; their vacuum package is capable of sustaining a cloud of cold atoms in a magneto-optical trap (MOT) for greater than 200 days using only non-evaporable getters and a rubidium dispenser. Measurements of the MOT lifetime indicate that the package maintains a pressure of better than 2 x 10-7 Torr. This result will significantly enable the development of compact atomic sensors, including those sensitive to magnetic fields, where the absence of an ion pump will be advantageous. [ABSTRACT FROM AUTHOR]