For many experiments performed at the cold-neutrons fundamental physics instrument PF1B at ILL, the polarizer is an essential component . Placed after the guide exit, it should produce a large-area, intense and well polarized “white” beam spanning a broad wavelength range (from 0.2 to 2.0nm). Until recently, a “Schaërpf-type” bender based on Co/Ti supermirrors was used, showing 98.5% polarization efficiency and about 50% transmission of "good" spin component. For higher polarization, the "crossed configuration"  could be used, yielding 99.7% polarization and 25% transmission. After more than 15 years of successful exploitation, the polarizer showed significant Co activation and noticeable damage of the mirrors. The present project aims at replacing the polarizer with a new one, having less operational drawbacks. The concept  is a more compact solid-state “V-bender”, based on Fe/Si supermirrors deposited in-house on sapphire substrates. Special care was taken to limit depolarization effects  and to minimize angular misalignments when stacking the mirrors. Following the concept validation with the first prototypes and measurements , the realization of the record-breaking  final device  will be described, including fabrication, neutron characterization preceding final installation on PF1B, and possibilities to extend the concept to other cases.
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