AMOR — the time-of-flight neutron reflectometer at SINQ/PSI

Abstract

The apparatus for multioptional reflectometry (AMOR) at SINQ/PSI is a versatile reflectometer operational in the time-of-flight (TOF) mode (in a wavelength range of 0.15 nm < λ < 1.3 nm) as well as in the monochromatic (θ-2θ) mode with both polarized and unpolarized neutrons. AMOR is designed to perform reflectometry measurements in horizontal sample-plane geometry which allows studying both solid-liquid and liquid-liquid interfaces. A pulsed cold neutron beam from the end position of the neutron guide is produced by a dual-chopper system (side-by-side) having two windows at 180 • and rotatable with a maximum frequency of 200 Hz. In the TOF mode, the chopper frequency, width of the gating window and the chopper-detector distance can be selected independently providing a wide range of q-resolution (∆ q/q = 1-10%). Remanent FeCoV/Ti : N supermirrors are used as polarizer/analyzer with a polarization efficiency of ∼97%. For the monochromatic wavelength mode, a Ni/Ti multilayer is used as a monochromator, giving ∼50% reflectivity at a wavelength of 0.47 nm. In the present work, a detailed description of the instrument and setting-up of the polarization option is described. Results from some of the recent studies with polarized neutrons and measurements on liquid surfaces are presented.

Adsorption of azacrown ethers at solid–liquid interface. Contact angle and neutron reflectivity study

“…The NR experiments at the neutron reflectometer AMOR [8] were performed in time-of-flight mode at three angles of incidence (0.38, 0.68, and 1.08) using a wavelength band from 2.2 to 5 Å , covering the necessary q range for the experiments of q z min = 0.01 Å À1 to q z max = 0.11 Å À1 . The resolution was set by a slit system on the incident side and the time-of-flight parameters to Dq z = 0.006 Å À1 .…”

“…Neutron reflectivity profile for Pt-covered Si/air together with the best-fit line. Table 1 The best-fit parameters for the neutron reflectivity from Si/Si-Pt/Pt/air, Si/Si-Pt/Pt/ toluene-D 8 Pt-covered Si (Si/Si-Pt/Pt) is, however, more hydrophobic, as is evident by comparison of contact angles of water on the freshly cleaned untreated Si/Si-Pt/Pt surface (37.9 AE 2.58. vs 30.9 AE 1.28 on bare Si/SiO 2 surface). The contact with toluene renders this surface even more hydrophobic with Q = 41.9 AE 5.18.…”

Fe and N diffusion in nitrogen-rich FeN measured using neutron reflectometry

“…The samples were characterized using X-ray diffraction (XRD) for the structure while thermal stability was examined using differential scanning calorimetry. Self-diffusion measurements were performed using neutron reflectometry in the time-of-fight mode at D17, ILL, Grenoble and AMOR at SINQ/PSI [7]. The samples were placed inside a specially designed vacuum furnace mounted on the sample stage of the reflectometer and the measurements were performed in the as-deposited state and at high temperatures.…”

New sources and instrumentation for neutrons in biology

“…Reflectometers at other facilities as HMI, LLB, JINR or LANSCE have also been used regularly on biological systems. Both at existing and new sources a number of instruments are being upgraded or under development, such as AMOR [43], a TOF reflectometer at SINQ, that can handle any kind of solid-liquid sample cell (e.g. a pressure device developed by the University of Heidelberg or a flow cell by TU Delft), or N + Rex at FRM II which combines neutron and X-ray reflectometry within one experiment.…”