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Neutrons at IBR-2. User meeting, June 2004, at FLNP/JINR Projet leader meeting, October 2004, at Uni Goettingen. Basis HFR IBR-2 user policy collaboration
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Neutrons at IBR-2 User meeting, June 2004, at FLNP/JINR Projet leader meeting, October 2004, at Uni Goettingen Basis HFR IBR-2 user policy collaboration Project REMUR:Investigation of the structure of nano-objects in films of magnetic and nonmagnetic materials including new Larmor precession devices Project Spin-Echo:Feasibility study of time-of-flight spin echo spectrometer at IBR-2. Project EPSILON/SKAT: Investigation of strain/stress and texture on geological samples Project YuMO: Investigation of nano - and mesostructures via small-angle neutron scattering HJL
Project DN-12: Neutron studies of microsamples under high pressure Project FSD:Internal stresses in functional materials studied by the high resolution Fourier neutron diffraction technique Project: DAQ and CI - Development of Data Acquisition Systems and Computing Infrastructure for the IBR-2 spectrometer complex. Project: Gas Neutron detectors HJL
Advanced Reflectometry with Larmor Precession Nanoscience Biology Horizontal Reflectometer Angular and Energy Encoding HJL
multilamellar vesicles for biochemical applications buried quantum dots stripe arrays MONITORING of the INTERNAlL STRUCTURE in VARIOUS NANOSYSTEMS imbedded nanoparticles in polymer matrix Nanowires in mesoporous silica magnetic multilayer films Nano-structures: needs for nano-characterization HJL
buried quantum dots multilamellar vesicles for biochemical applications stripe arrays MONITORING of the INTERNAlL STRUCTURE in VARIOUS NANOSYSTEMS imbedded nanoparticles in polymer matrix Nanowires in mesoporous silica magnetic multilayer films Nano-structures “as seen” by neutrons Information about the transverse and lateral structure (magnetic and non-magnetic) is encoded in the 2D scattered intensity -> comprehensive data analysis is needed HJL
The principle of Neutron Spin Echo Sample Polarization analyzer Detector Polarizer (supermirror, Heusler) Precession magnetic fields (solenoids) HJL
The principle of Neutron Spin Echo Sample HJL
Magnetic field H polarized neutrons Q n Q S2 S1 l Current sheets Detector Analyzer Larmor precession for encodingl and Q vn Pulsed white beam Sample position outside (s1) or inside (s2) LP-device (s1) sensitive to l and Q (s2) H perpendicular to P; scattering f(M) (s3) divergent incoming beam for GISANS Larmor precession angle F =gLlH/vn gL=2.916 kHz/Oe HJL
Encoding of l with LP-device Reflected beam Direct beam H Det.AnalyzerSample LP-device Res. spin flipper Top view Polymerfilm sample Reflected Direct HJL
Encoding of l with LP-device Reflected beam Direct beam H Det.AnalyzerSample(after LP) LP-device Res. spin flipper H = 20Oe l = 0.473m Polymerfilm sample Spin-asymmetry SA = (I+-I-)/(I++I-) *direct and reflected beams in phase* spin up H=18.8 Oe derived from oscillations HJL
Encoding of l with LP-device Reflected beam Direct beam H Det.AnalyzerSample LP-device Res. spin flipper Polymerfilm sample H=18.8 Oe H=17.5 Oe HJL
Encoding of l as a function of H SA for H=17.5 Oe SA for H=17.5 Oe and H=18.8 Oe Polymerfilm sample SA (H=17.5 Oe) - SA(H=18.8 Oe) HJL
Encoding of l with LP-device--gain in intensity Incoming converging beam Overlapping but encoded signal Reflected beam Direct beam H Det.AnalyzerSample LP-device Res. spin flipper Top view Polymerfilm sample Reflected Direct HJL
Reflected beam H Sample Direct beam Det.AnalyzerLP-device Res. spin flipper Reflectometry with Larmor precession Fe-Cr multilayer sample inside LP-device Fe-Cr sample - “AF” ordered - near remanent field HJL
magnetization M1 spin rotation axis M2 Determination of the total magnetic moment and its direction Determination of the layer-by-layer magnetization Out-of-plane (and in-plane) Larmor precession Simultaneous measurement with in-plane and out-of-plane spin direction Access to out-of plane magnetisation and full depth profile of in-plane magnetisation HJL
Advanced Reflectometry with Larmor Precession Angular and Energy Encoding for Nanoscience REMUR equipment including neutron guide and cold moderator Reflex equipment (cold moderator) Biology-Horizontal Reflectometer Note:Study for investigation of 3rd co-ordinate (GISANS) HJL
Advanced Reflectometry with Larmor Precession V.Lauter-Pasyuk TU München W.Petry TU München M.Jernenkov ILL Grenoble H.J.Lauter ILL Grenoble A.Ioffe FZ Jülich T.Brückel FZ Jülich P.Schmiedel Uni Halle K.Jernenkov FLNP Dubna V.Bodnarchuk FLNP Dubna A.Petrenko FLNP Dubna V.Aksenov FLNP Dubna A.Belushkin FLNP Dubna HJL
Top view of IN3 with spin echo option ZETA mumetal shield sample area coupling coils monitor counter PG-filter Heusler analyzer double RF-flippers (bootstrap coils) 1 m Heusler monochrom. B Residual internal field ~ 5 mG. „Precession“ length - 55 cm Frequency range 50 – 750 KHz corresponds to effective fields 35 G – 1 KG 3He detector HJL
Three axis spectrometer IN3 with spin echo option ZETA. The magnetic shields are opened to show the two flipper coils in each arm double RF-flippers (bootstrap coils) HJL