SEMIRAMIS operates an ion beam platform dedicated to pluridisciplinary physics and chemistry

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1 SEMIRAMIS Since the sixties, the SEMIRAMIS group has developed skills concerning ion sources and ion beam handling from few hundred ev up to around 10 MeV, with the purpose of materials implantation, irradiation and analysis, and isotope separation for target creation. The equipment available is: a 2MV Van de Graaff/Tandem accelerator, ARAMIS; a 190kV implantor, IRMA; a 50kV isotope separator, SIDONIE; and 200kV Transmission Electron Microscope, TEM. Since 2009, the JANNuS-Orsay platform has started and provides each year 12 weeks of beam-time for experimental projects selected by the EMIR, a national network concerning material studies under irradiation. The following describes the JANNuS-Orsay facility and its integration inside the EMIR network, the instruments managed by the department and finish with a summary of the beam time s use. Members: C. Bachelet, C.O. Bacri, C. Baumier, J. Bourçois, L. Delbecq, O. Kaitasov, J. Moeyaert, E. Oliviero, N. Pauwels, S. Picard, S. Renouf. JANNuS/EMIR (introducing SCALP) SEMIRAMIS operates an ion beam platform dedicated to pluridisciplinary physics and chemistry such as astroparticles, materials for nuclear energy, nuclear physics, solid physics, physico-chemistry of materials, microelectronics, nanosciences, earth sciences... It is composed of a 2 MV Tandem/Van de Graaf Accelerator (ARAMIS) and a 190 kv ion implantor (IRMA), both being possibly coupled to a 200 kv Transmission Electron Microscope (TEM FEI TecnaiG2 20) allowing in-situ observation of irradiation effects (Figure 1). This coupling, JANNuS-Orsay, is part of a multi-ion beam irradia- Figure 1 Schematic view of the SCALP platform. Coupling of ARAMIS, IRMA and the MET constitutes JANNuS-Orsay. tion platform called JANNuS ( fr/), and managed by CEA/DEN, CEA/INSTN, CNRS/ IN2P3 and Paris-Sud University, in the framework of a Scientific Interest Group (GIS). JANNuS is part of the EMIR network ( which consist of five accelerator platforms dedicated to material irradiation with a shared scientific committee. JANNuS-Orsay is mainly used for controlled modification or synthesis of materials at the nanoscale by ion implantation and irradiation, simulation of radiation damage in nuclear materials, and education and training in the field of particle-matter interactions and its applications. CSNSM platform also operates a 50 kv electromagnetic isotope separator, SIDONIE, which is primarily used for the separation of high purity thin deposit and targets, mainly for nuclear physics experiments. Since 2015, all these CSNSM machines constitute the SCALP (Synthesis and Characterization using ion AcceLeration for Pluridisciplinary research) platform (Figure 1). It allows performing irradiation/ implantation, ion beam analysis, and target production for the study of elementary mechanisms governing the behavior of materials under irradiation. SCALP is managed through a technical and scientific committee, which examine the beam time requests, while maintaining flexibility in the management of the beam time. The platform is also used for education and training in the field of particle-matter interactions and its applications, through organization of Travaux Pratiques and trainees. Part of the beam time is also dedicated to some industrials needs of irradiations/implantations.

2 ARAMIS ARAMIS is a home-made 2MV s accelerator, for materials implantation/irradiation and ion beam analysis, in activity since ARAMIS can be used as a Van de Graaff accelerator; with a Penning ion source located at the high voltage stage and provides gaseous elements like hydrogen, helium, nitrogen or oxygen. ARAMIS can be used also as a Tandem, with the Middleton negative ion source at the ground potential and provides more than forty different elements. See Figure 3 for the elements available with ARAMIS. Three beam lines are available for different type of experiments. The characterization line is used for ion beam analysis of materials. A goniometer, with 2 translations and 2 rotations, allows characterization of several samples in the same run, and channelling inside the material s crystal. The ion beam analysis methods available are C/RBS, ERDA and PIXE. After a previous update of the goniometer with a PMC Multiflex card, instead of an old RS232 controller, and a LabView based user interface, the purchase of a new goniometer is on going, with the participation of the Physics and Chemistry of Irradiation group. The commissioning of the goniometer should be done within the first trimester of The C/RBS acquisition analogic system has also been replaced with a CAEN N1728B. This module allows signal digitizing from the preamplifier on 4 channels. A new user acquisition interface has been developed using LabView. The possibility to use 4 detectors at a time is currently in development. This option will reduce the acquisition time or increase the counting rate of the spectra. Finally, PIXE analysis has been added two years ago. Two silicon drift detectors (SDD) open the possibility to detect elements from beryllium to uranium. The implantation/irradiation beam line is used for materials modifications with several conditions. Different sample holders are available and permit to do materials implantation/irradiation with temperature running from 77K to 1200K. Another sample holder allows the implantation/irradiation on different samples with different parameters in the same run, with holders like the Translation, the Revolver or the Airlock. The third beam line is called the JANNuS line. This line is a connection from ARAMIS to the Transmission Electron Microscope (TEM). It allows in situ studies of materials implantation/irradiation under double ion beam of ARAMIS and IRMA (see JANNuS section). In 2015, the commissioning of a beamline linking ARA- MIS to IRMA has been done. Using +/-50 kv deflectors, we can drive a high energy beam, from ARAMIS, into the IRMA s irradiation chamber (Figure 2). With samples placed on a goniometer, the beamline allows in situ RBS/C of materials during irradiation. Figure 2 Electrostatic deflectors, driving the ARAMIS beam inside IRMA s irradiation chamber IRMA IRMA is an ion implanter of 190kV, home-made in IRMA can provide ion beam energy from 5 to 570 kev. Its Bernas-Nier ion source can produce almost all stable elements (Figure 3), with a current up to 100 µa. The purpose of IRMA is principally materials modification by ion implantation, in several conditions. The sample holders, available for IRMA, are the same as the one described in the ARAMIS section. During the last years, and taking advantage of the JANNuS platform development, IRMA had several updates and improvements. For example, the beam line after the acceleration section has been rejuvenated and now all the components at ground potential are computer-driven, and some at the high voltage stage. A complete migration to a digital control has been done in The moving electrode for ion extraction of the source has been replaced. A complete new design with motorised and independent moves has been developed in collaboration with the mechanical Figure 3 Elements available with ARAMIS-IRMA 6 CSNSM - SEMIRAMIS 89

3 Figure 4 New moving electrode for ion extraction on IRMA. department (Figure 4). The installation of this electrode has been coupled with the control update, since the moves is now computer-driven. The electrode is now sold to Ion Beam Service to be used as a part of their new implanter. Transmission Electron Microscope (TEM) Figure 5 Schematic view of the separator SIDONIE The TEM of the CSNSM is part of the JANNuS-Orsay platform and has been designed for dual-irradiation/ implantation in-situ and dynamic experiments. The TEM is a FEI Tecnai G 2 20 Twin. The electron beam is extracted from a LaB 6 filament and the accelerating voltage can be set from 80 to 200 kv. The spatial resolution is 0.27 nm. This microscope is equipped today with 2 CCD cameras for imaging (a wide angle & high resolution camera). For the spectroscopy measurement the TEM proposed several techniques : EDX, EELS, EFTEM and a STEM (scanning transmission electron microscopy) mode with HAADF and BF-DF which allow the Spectrum Imaging (SI) with the coupled EELS and EDX measurement. In the best conditions, the energy resolution for the EELS is 1,1 ev. Since the end of 2015, all these techniques of measurements and analysis are available in dynamics with the video recording (when the ions beam is suitable with the Magnetic field of the TEM polar piece). The TEM of the platform is also equipped with several sample holders which allow double tilt and rotation; and a wide range of temperature from -170 C to 1300 C. Many sample holders are ultra-thin, a design dedicated to in situ irradiation. In order to keep the platform as a highly ranked in situ analysis facility, further development is foreseen (see Research, Development & Perspectives chapter). This TEM of JANNuS-Orsay is also accessible by the annual EMIR call, which allows scientists from all around the world to have their experiments granted. The experiments done on the microscope concern the fields of nuclear simulation, materials sciences, nanotechnology, semiconductors, nano-particles, amorphization/recrystallization, inorganic chemistry SIDONIE SIDONIE is an electromagnetic isotope separator, which is primarily used for the preparation of high purity thin deposit and targets, mainly in nuclear physics experiments. The separator is composed of a Bernas-Nier ion source, a high resolution analyzing magnet and a collecting device, which is used to prepare targets with the selected ion beam. A picture of the SIDONIE experimental apparatus is represented in Figure 5. The source can deliver almost all ions. They are mainly single-charged and the extracted beam intensity ranges from a few ma up to 20 ma. Their energy are typically around 40 kev. The separation power of the analyzing magnet is 1000, which means that masses 100 and 101 are separated with 1 cm in the focal plane. In order to complete the possibilities of the separator, a new setup has been installed. It consists in a near visible infrared spectrometer coupled with the beam line of SIDONIE. Called INGMAR (IrradiatioN de Glaces et Météorites Analysées par Réflectance VIS-IR), it was funded in close collaboration with the IAS (Institut d Astrophysique Spatiale). It allows analysing the molecular structure of samples under irradiation and is mainly used to understand the ageing of micrometeorites under irradiation by solar wind. 90 CSNSM - SEMIRAMIS

4 Beam Time Summary There are three ways of assignment of the beam time: via the yearly EMIR call for proposals; via the SEMIRAMIS council call every three months; or via the along the way time allocation versus payment. The use of ARAMIS and IRMA is between 140 and 160 days per year (Figure 6). ARAMIS is mainly used, around 60%; IRMA represents 23% and the dual beam represents 17%. The need of a more often maintenance of IRMA explains the difference of time use compared to ARAMIS. One day represents generally one experiment and lasting roughly 8 hours. Between 30% and 40% of the time is used for CSNSM s research (Figure 7). Around the same amount is dedicated to experiments granted by the EMIR s scientific council. Outside the EMIR s network context, external users can have access to the platform as a paid service; with academic fee for University and CNRS members and full fee for the others. These external users represent 28% of the total beam time, industrials around 10%. Teaching activities on the platform are slightly rising along the years. Our human-scale devices allow original and high technicality practical works for master s students. Teaching, using SCALP facility, is delivered by the SEMIRAMIS team or members of the Physics and Chemistry of Irradiation and Solid State Astrophysics research groups, and concerned several Masters of Université Paris-Saclay: Nuclear Energy, Physics and Engineering of Energy, Astronomical and Spaced-based Systems Engineering and recently Grands Instruments. Figure 6 Days of use of ARAMIS, IRMA and Dual-Beam Figure 7 Split of beam time allocation 6 Research, Development & Perspectives The SEMIRAMIS team has usually, in the past years, focussed on several research subjects, using its analytic capabilities. Recently, He diffusion in apatite studies, within the ANR HeDiff project, or oxygen density measurements in rareearth based cuprates superconductors were investigated. In addition to the Ion Beam Analysis techniques already used (RBS, ERDA, PIXE), the group aims to provide another technique called micropixe. MicroPIXE is an extension of PIXE (Particleinduced X-ray emission) using a beam focused down to 1 µm. The solution retained for the focusing system was not the classical one, using magnetic quadripole lenses, but a simple and low-cost method, using a tapered glass capillary. Figure 8 Split of the TEM use CSNSM - SEMIRAMIS 91

5 It is expected to complete the setup by summer 2016 and to carry out first micropixe experiments by the end of It will then be possible to produce elemental maps of samples e.g. for the astrophysics and geological communities. Once the micropixe technique available, a next step could be to investigate in-air analysis. This development has been funded by Paris-Sud university through the 2014 project call Equipement de Recherche Mutualisée, with the collaboration of the GEOPS laboratory, under the coordination of Céline Tanguy. The development of PIGE applications has been also initiate, in order to extend the scope of the platform and meet the needs of many scientific communities. Two channels are currently being explored: - the production of high-energy γ beam (up to 16 MeV) allowing the calibration of detectors, - the analysis method for determination of hydrogen and isotopic light elements in various samples. These new developments are under the coordination of Nicolas Pauwels. In order to extend in situ capabilities of the TEM, the project POMETILAT aim to build a new sample holder. POMETILAT consists a laser waveguide coupled to a heating element in the very thin manifold of the (3 mm diameter). This new tool will allow the in-situ study of the dynamics of structural changes resulting from photo-induced d-d electron charge transfert. This development is motivated by the study of Prussian Blue Analogues (ABP) photoswitchable molecular systems whose magnetic properties offer attractive prospects for the storage of high-density information. POMETI- LAT is funded by the interdisciplinary mission of the CNRS through the 2015 project call DEFI Instrumentation aux limites with the collaboration LCI/ICMMO, under the coordination of Cedric Baumier. Figure 9 Technical drawing of the POMETILAT sample holder 92 CSNSM - SEMIRAMIS

6 Publications PUBLISHED PAPERS Debelle A., Boulle A., Rakotovao, F. et al. Infl uence of elastic properties on the strain induced by ion irradiation in crystalline materials, J. Phys. D Appl. Phys. 46 (2013) Pauwels N., Horodynski J.M., Robert P., Tadjeddine A. Decommissioning of the LURE Nuclear Facility, Radioprotection 48 (2013) 545 Thome L., Debelle A., Garrido F. et al. Radiation effects in nuclear materials: Role of nuclear and electronic energy losses and their synergy, Nucl. Instr. Meth. in Phys. Res. B 307 (2013) 43 Chiuzbaian S.G., Hague C.F., Avila A. et al. Design and performance of AERHA, a high acceptance high resolution soft x-ray spectrometer, Rev. Sci. Instrum. 85 (2014) Roedel T.C., Bareille C., Fortuna F. et al. Orientational Tuning of the Fermi Sea of Confi ned Electrons at the SrTiO3 (110) and (111) Surfaces, Phys. Rev. Appl. 1 (2014) Sabathier C., Martin G., Michel A. et al. In-situ TEM observation of nano-void formation in UO2 under irradiation, Nucl. Instr. Meth. in Phys. Res. B 326 (2014) 247 Tien Hien N., Garrido F., Debelle A. et al. Radiation damage in urania crystals implanted with low-energy ions, Nucl. Instr. Meth. in Phys. Res. B 326 (2014) 264 Bergeard N., Schaffert S., Lopez-Flores V. et al. Irreversible transformation of ferromagnetic ordered stripe domains in singleshot infrared-pump/resonant-x-ray-scattering-probe experiments, Phys. Rev. B 91 (2015) Defresne A., Plantevin O., Sobkowicz I.P. et al. Interface defects in a-si:h/c-si heterojunction solar cells, Nucl. Instr. Meth. in Phys. Res. B 365 (2015) 133 Sengupta, S.; Li, C.; Baumier, C.; Kasumov, A.; Gueron, S.; Bouchiat, H.; Fortuna, F. Superconducting nanowires by electron-beam-induced deposition, App. Phys. Lett. 106 (2015) PROCEEDINGS Fang L., Bachelet C., Sagnes, I. et al. Ion implanted In0.53Ga0.47As for ultrafast saturable absorber device at 1.55 mu m, 26 th International Conference on Indium Phosphide and Related Materials (IPRM) (2014) CSNSM - SEMIRAMIS 93