Synchrotron-based Bragg coherent x-ray diffraction (CXD) measurements proposed to study giant magnetorestriction in nickel NW: (a) Monochromatic X-ray beam is focused by Kirkpatrick-Baez mirrors, which creates a localized illumination on the sample (S). By rotating the sample through the Bragg condition in increments of about 0.005 degrees, CXD patterns in the vicinity of the (111) and (002) reciprocal lattice points are recorded with a two-dimensional pixelated detector. A series of diffraction patterns (collected as a function of external magnetic field H) are shown here. The interference fringes are due to the finite extent of the nanowire. The color scale is calibrated in units of X-ray photons per pixel; the center of the pattern reaches a value of 9,000, but is saturated here. (b) SQUID-hysteresis loops of a 200 nm wide and 2 micron long nickel nanowire measured with an applied field at room temperature. (c) Relative change in the lattice spacing (corresponding to the asymmetry and shift of the center of mass of the measured Bragg peaks) along the < 100 > direction and the < 110 > directions. Measurements are taken during a cyclic loading (increasing magnetic field strength) and unloading procedure.
- Anastasios Pateras
- Ross Harder
- Edwin Fohtung
