Polarizing Supermirror Assembly Systems (PSAS) for Advanced Neutron Beam Optics

To offer US neutron facilities a superior domestic product at reduced prices, Phase III Physics LLC (P3P) will develop Polarizing Supermirror Assembly Systems (PSAS) utilizing magnetic multilayer thin film deposition. The PSAS will be composed of stacked supermirror substrates arranged in the solid state V-bender configuration, capitalizing on the simplicity of assembly, blade alignment, and compactness compared with other polarizer assemblies. During Phase-I, P3P will enlist the help of an independent contractor, mechanical engineer Dr. Walter J. Fox, to aid in the design of our assembly fabrication equipment as well as our in-house sputtering configuration. Dr. Fox’s designs will be guided by P3P simulations and experimental neutron reflectometry and polarization studies performed at ORNL. Manufacturing feasibility studies will be performed in-house at our facility in Downtown Los Angeles. To find optimal sputtering conditions for the magnetic supermirror coatings, we will continue our collaboration with the Hodge Materials Research Group at the University of Southern California (USC) led by Professor Andrea Hodge, who assisted us in the development of Ni/Ti multilayer supermirrors for neutron guide design. The group will synthesize and characterize thin film samples composed of Si/Fe bilayer structures under a variety of basic and reactive sputtering conditions onto Silicon and Sapphire substrates targeting a neutron momentum transfer cutoff of m=4, reflectivity of 80%, and polarizing efficiency of 90% for cold neutrons. The deposition recipes will be created by theoretical physicist Dr. Akhil Sheoran and experimental neutron physicist Dr. Christopher Haddock at P3P, who have experience in creating such recipes for ordinary, non-magnetized supermirror substrates, and understand the critical and nontrivial differences between the two. This effort will be led by P3P founder Dr. Christopher Haddock who is established in the field of fundamental neutron physics and, in particular, polarized neutron beam manipulation, and will leverage his experience to rapidly field test and improve upon prototypes for optimal functionality using neutron beamlines in the U.S.