GammaRay 2018 Proceedings: Seminar for users of gamma ray spectrometry

In September 2018 a two day seminar for users of gamma ray spectrometry was arranged in Reykjavik, Iceland. 34 participants from 20 organisations were present. Two lecturers were invited: I. Osvath from IAEA, who gave a presentation on the 2017 IAEA proficiency test with a focus on the sample with the more challenging short lived radionuclides, and M. Bruggeman from SCK-CEN, who gave a presentation on efficiency transfer for low-energy gamma-ray spectrometry. In addition, 14 participants presented development and experiences related to gamma-ray spectrometry. This seminar was the 9th in a serie since 2009 financed by NKS

Superconductivity on the localization threshold and magnetic-field-tuned superconductor-insulator transition in TiN films

Temperature- and magnetic-field dependent measurements of the resistance of ultrathin superconducting TiN films are presented. The analysis of the temperature dependence of the zero field resistance indicates an underlying insulating behavior, when the contribution of Aslamasov-Larkin fluctuations is taken into account. This demonstrates the possibility of coexistence of the superconducting and insulating phases and of a direct transition from the one to the other. The scaling behavior of magnetic field data is in accordance with a superconductor-insulator transition (SIT) driven by quantum phase fluctuations in two-dimensional superconductor. The temperature dependence of the isomagnetic resistance data on the high-field side of the SIT has been analyzed and the presence of an insulating phase was confirmed. A transition from the insulating to a metallic phase is found at high magnetic fields, where the zero-temperature asymptotic value of the resistance being equal to h/e^2.Comment: 5 pages, 4 eps figures, RevTeX4, Published versio