M-STAR: Magnetism second target advanced reflectometer at the Spallation Neutron Source

Valeria Lauter; Kang Wang; Tim Mewes; Artur Glavic; Boris Toperverg; Mahshid Ahmadi; Badih Assaf; Bin Hu; Mingda Li; Xinyu Liu; Yaohua Liu; Jagadeesh Moodera; Leonid Rokhinson; Deepak Singh; Nian Sun

doi:10.1063/5.0093622

M-STAR: Magnetism second target advanced reflectometer at the Spallation Neutron Source

Rev Sci Instrum. 2022 Oct 1;93(10):103903. doi: 10.1063/5.0093622.

Authors

Valeria Lauter¹, Kang Wang², Tim Mewes³, Artur Glavic⁴, Boris Toperverg⁵, Mahshid Ahmadi⁶, Badih Assaf⁷, Bin Hu⁶, Mingda Li⁸, Xinyu Liu⁷, Yaohua Liu⁹, Jagadeesh Moodera⁸, Leonid Rokhinson¹⁰, Deepak Singh¹¹, Nian Sun¹²

Affiliations

¹ Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, USA.
² Department of Electrical and Computer Engineering, Department of Physics, Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, USA.
³ Magnetics Laboratory, Department of Physics and Astronomy, The University of Alabama, 1008 Bevill Bldg., Tuscaloosa, Alabama 3548, USA.
⁴ Laboratory for Neutron and Muon Instrumentation, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland.
⁵ Department of Solid State Physics, Experimental Physics, Ruhr-University Bochum, Universitetsstrasse 150, Bochum D-44781, Germany.
⁶ Department of Materials Science and Engineering, Institute for Advanced Materials and Manufacturing, University of Tennessee, 2641 Osprey Vista Way, Knoxville, Tennessee 37920, USA.
⁷ 225 Nieuwland Science Center, University of Notre Dame, Notre Dame, Indiana 46556, USA.
⁸ Massachusetts Institute of Technology, 77 Massachusetts Ave., Bldg. 24-209, Cambridge, Massachusetts 02139, USA.
⁹ Second Target Station, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, USA.
¹⁰ Department of Physics, Purdue University, West Lafayette, Indiana 47906, USA.
¹¹ 223 Physics Building, Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA.
¹² Electrical and Computer Engineering Department, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, USA.

PMID: 36319315
DOI: 10.1063/5.0093622

Abstract

M-STAR is a next generation polarized neutron reflectometer with advanced capabilities. A new focusing guide concept is optimized for samples with dimensions down to a millimeter range. A proposed hybrid pulse-skipping chopper will enable experiments at constant geometry at one incident angle in a broad range of wavevector transfer Q up to 0.3 A^-1 for specular, off-specular, and GISANS measurements. M-STAR will empower nanoscience and spintronics studies routinely on small samples (∼2 × 2 mm²) and of atomic-scale thickness using versatile experimental conditions of magnetic and/or electric fields, light, and temperature applied in situ to novel complex device-like nanosystems with multiple buried interfaces. M-STAR will enable improved grazing incidence diffraction measurements, as a surface-sensitive depth-resolved probe of, e.g., the out-of-plane component of atomic magnetic moments in ferromagnetic, antiferromagnetic, and more complex structures as well as in-plane atomic-scale structures inaccessible with contemporary diffractometry and reflectometry. New horizons will be opened by the development of an option to probe near-surface dynamics with inelastic grazing incidence scattering in the time-of-flight mode. These novel options in combination with ideally matched parameters of the second target station will place M-STAR in the world's leading position for high resolution polarized reflectometry.