We have succeeded in growing sizable single crystal of Bi_2+xSr_2-xCuO_6+y (Bi2201) High-T_c cuprates by improving frosting-zone method. Inelastic neutron scattering measurements on the single-layer cuprate Bi2201 with x=0.2, 0.3, 0.4 and 0.5 reveal existing of magnetic excitation signal at around (0.5, 0.5). The doping evolution of low energy magnetic excitation (ω ≦ 11 meV) was found as a change of incommensurate modulation wave vector from the [110] to [100]/[010] directions, and a linear relationship between the incommensurability and the hole concentration, δ~ p. On the other hands, the spectral weight is strongly suppressed with increasing hole concentration. Similarities and differences in the spin correlations between Bi2201 and the prototypical single-layer system La_2-xSr_xCuO₄ are discussed.

Interactions between electrons carrying various degrees of freedom are relevant to physical properties and phase transitions in materials. Inelastic neutron spectroscopy for crystal field excitations is meaningful to resolve the electronic interactions. In this article, some example results for rare-earth metallic compounds are briefly shown.

X-ray and neutron reflectometry are powerful techniques for observing depth profiles of surfaces and interfaces on the scale from nanometers to sub-micrometers in a non-destructive manner. In particular, neutrons can penetrate materials, distinguish isotopes, and have magnetic spin moment. This enables us to observe protein structure, especially for the interaction with phospholipid bilayers, with special techniques. In this review, we introduce two protein studies using neutron reflectometry: one is the cholera toxin CTAB₅ in contact with a Langmuir monolayer of phospholipid/ganglioside mixture, and the other is the Escherichia coli outer membrane protein OmpF supported on a gold surface with a thiolipid/phospholipid bilayer.

  Neutron radiography is expanding from the conventional reactor based imaging to the imaging by accelerator based pulsed neutron source. Among them, an expectation for image intensifier technology is increasing especially for video rate dynamic image detection or time dependent imaging in a pulsed neutron source. Based on the X-ray color image intensifier technology, Toshiba has developed neutron color image intensifiers as a powerful imaging tool for dynamic and time dependent neutron radiographies. In this paper, the construction and the feature of the developed neutron color image intensifier and some examples of neutron images are presented. I would be grateful if this paper helps for wide application of neutron color image intensifiers.