Isotopic control of the boron-vacancy spin defect in hexagonal boron nitride

We report on electron spin resonance (ESR) spectroscopy of boron-vacancy (V$_\text{B}^-$) centers hosted in isotopically-engineered hexagonal boron nitride (hBN) crystals. We first show that isotopic purification of hBN with $^{15}$N yields a simplified and well-resolved hyperfine structure of V$_\text{B}^-$ centers, while purification with $^{10}$B leads to narrower ESR linewidths. These results establish isotopically-purified h$^{10}$B$^{15}$N crystals as the optimal host material for future use of V$_\text{B}^-$ spin defects in quantum technologies. Capitalizing on these findings, we then demonstrate optically-induced polarization of $^{15}$N nuclei in h$^{10}$B$^{15}$N, whose mechanism relies on electron-nuclear spin mixing in the V$_\text{B}^-$ ground state. This work opens up new prospects for future developments of spin-based quantum sensors and simulators on a two-dimensional material platform.Comment: 6 pages, 3 figur

Elimination de l'ammoniaque dans les eaux residuaires

SIGLECNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Ecoulements non stationnaires par la methode des elements finis

SIGLECNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Matieres organiques dans les eaux naturelles: cas des produits organiques azotes

SIGLECNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Quality of life in adult survivors of correction of esophageal atresia

Hypothesis: Long-term quality of life (QOL) in adults after correction of esophageal atresia (EA) is comparable with that of healthy adults. Design: Outcome study with a consecutive sample and follow-up after 16 years or longer. Setting: Pediatric surgical center (academic center) in a tertiary hospital. Patients and Methods: A questionnaire was sent to 119 consecutive surviving adults who were treated for EA between 1947 and 1986. The questionnaire was to assess sociodemographic characteristics and generic and disease-specific QOL and contained 3 open-ended questions about the consequences of the disease in daily life. Clinical characteristics were collected from patient case notes. Results: Ninety-seven (82%) of the 119 questionnaires were completed and returned. When comparing the generic QOL of patients who had EA with that of healthy subjects, we found no differences in overall physical and mental health. The presence of concomitant congenital anomalies did not influence generic QOL. A third of the patients reported that EA had had negative effects on their daily lives. Gastrointestinal symptoms such as dysphagia were most often mentioned (23%). Conclusion: In general, after EA correction, patients perceive their generic and disease-specific QOL to be good. The presence of concomitant congenital anomalies did not influence generic QOL. However, a third of patients reported that the disease had had negative consequence

Photon emission from STM of granular gold in UHV: comparison with air and study of spectra shifting with tip position

This paper presents an experimental study using photon emission derived from scanning tunnelling microscopy (STM) of a granular gold surface in Ultra High Vacuum (UHV). The aim is to make a comparison with previous results obtained in air or in UHV. The photon emission spectrum also evidences a significant energy shift as the tip moves on a surface grain. This shift is attributed to the local geometry of the junction and to peculiar crystallographic properties of the surface

L'Etat et les entreprises. La lutte anti-pollution dans le secteur des cimenteries

CNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

Environnement et emploi: le contenu en emploi des grands travaux d'assainissement: etude de cas

CNRS-CDST / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc