- Inelastic Neutron Scattering
- You must be registered as a radiation worker at your own institute.
- The date of radiation safety education and training at your institute must be within one year before registration (October 2023).
- The date of medical examination at your institute must be within a period in the following table before registration (October 2023).
|Category||Employee at a Japanese institute||Employee at a
|Period||Half a year||One year (MLF)
Half a year (JRR-3)
Inelastic Neutron Scattering
Inelastic neutron scattering is an experimental method that is used to observe micro-vibration (dynamics) of atoms and spins in a material. By observing the difference in energy between the incident and scattered neutrons, the magnitudes, distances, and directions of the forces acting between the atoms or spins in the material can be determined.
In this course, students will learn how to measure collective vibrations of atoms (phonons) or spins (magnons) in a single crystal as a function of momentum and energy by inelastic neutron scattering using the chopper spectrometer 4SEASONS. By analyzing the data, students will learn what kinds of forces act between atoms or spins and how they affect the macroscopic properties.
Quasielastic neutron scattering enables us to observe ion, atomic, and spin dynamics over a wide dynamic range from picoseconds to nanoseconds.
In this course, participants will learn how to prepare and measure samples (Nafion as a proton exchange membrane), and how to analyze data.
PDF analysis under high pressure
PLANET is the diffractometer dedicated to various high pressure experiments including structure analysis of crystals, liquid and amorphous solids.
This course offers practical training of PDF analysis under high pressure:
- Compression of water with a Paris-Edinburgh press
- Measurements of compressed water and a high-pressure polymorph of ice (ice VII)
- Determination of the lattice parameter of ice VII and estimation of the generated pressure
- PDF analysis of compressed water and ice VII
- Investigating the difference of hydrogen bonds between these phases.
Materials strength by neutron diffraction
Careful analysis of the Bragg peaks in a neutron diffraction pattern can reveal important structural details of a sample material such as internal stresses, phase conditions, dislocations, texture etc. Such information is often crucial in engineering applications and the ability to carry out either ex-situ or in-situ measurements makes neutron diffraction particularly useful in this respect.
In this course, students will learn how to measure, analyze data, and understand phenomena in in situ neutron diffraction experiments of metallic materials under deformation or residual stress measurement experiments of mechanical parts.
At surfaces and interfaces where different materials are in contact with each other, they show characteristic properties and various functions due to their peculiarity, which attract chemists, biologists, and physicists. Neutron reflectometry (NR) is a powerful tool for investigating the surface and interfaces of soft matters, magnetic materials etc. at a length scale of nanometers. Neutrons can distinguish an interesting part labeled with deuterium and/or can observe an interface between solid and liquid through a substrate. Polarized neutron reflectometry can observe magnetic moment behavior on the surfaces and interfaces of magnetic materials.
In this course, students will perform an experiment of the NR with polarized neutrons using the SHARAKU reflectometer. The structure of magnetic thin films and polymer membrane on silicon substrates will be analyzed according to the Parratt formalism.
Positive muon spin relaxation (μSR)
Positive muon in a material stops at an interstitial site, observes magnetic fields of the environment and exhibits Larmor spin precession. By measuring the decay positrons emitted from muons, time dependent behavior of the muon spin in a material is known. This is the spectroscopy called (positive) muon spin relaxation (μSR). This technique yields the information of the magnetic property of a material, including magnetism and superconductivity and the hydrogen state in a material with the muon being a light hydrogen isotope.
In contrast to neutron, muon is a local magnetic probe in real space with a unique time scale, being a powerful probe of spin relaxation phenomena.
In this course, students will perform simulated μSR measurement at the S1-ARTEMIS spectrometer and will receive instruction of data analysis. Introductory lectures on μSR and other muon measurements will also be given as a part of the school.
Ultra-Slow Muon Spin Spectroscopy
Muons find extensive application in materials science as spin-polarized quantum beams. Muon spin rotation/relaxation/resonance (μSR) is an experimental method to implant muons into materials for probing local magnetic fields. The muon beams primarily used in μSR experiments are obtained from pion decays at the surface of the production target. These beams are so-called surface muons and exhibit near-perfect polarization and monochromaticity. Nevertheless, due to their high energy of 4 MeV, measurements on thin samples using a surface muon beam are challenging. In this regard, low-energy muons have advantageous for measurements with thin-film samples and studies on interfaces.
The ultra-slow muon (USM) beamline at MLF MUSE provides a low-energy muon beam via laser ionization of thermal muonium in a vacuum. At the U1A experimental area, a muon spin spectrometer is located on a high-voltage platform to control the muon implantation energy. USMs can be selectively implanted on surfaces and interfaces in materials, enabling depth-resolving μSR. Furthermore, the time width of the beam is much narrower than that of the pulsed proton beam, so the frequency range of observable dynamics is wide.
In this course, participants will learn the mechanism of USM generation, the transport scheme, and experience USM-μSR with a thin-film sample.