Neutron super mirror

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A neutron super mirror is a mirror that is used in neutron conduction and that increases the maximum angle of reflection of the neutrons . The reflection up to the critical angle of the uppermost layer material comes about through the actual total reflection , followed by the maxima of the Bragg reflection , which decrease with increasing angle of incidence. The mirror is made up of several layers of different metals (usually two) that are applied to a glass or silicon substrate. The layer thickness decreases towards the substrate. One uses z. B. silicon , nickel , titanium or alloys thereof. The substrate is usually coated by cathode sputtering . Neutron super mirrors can be designed in such a way that they can be used to separate spin- up and spin-down neutrons, i.e. to generate a polarized neutron beam. For this, one of the layer materials must be ferromagnetic and the super mirror must be in a magnetic field. The effect used is the splitting of the scattering length density of the magnetic material.

literature

  • F. Mezei: Novel polarized neutron devices: supermirror and spin component amplifier . In: Communications on Physics (London) . tape 1 , no. 3 , 1976, p. 81-85 .
  • F. Mezei, PA Dagleish: Corrigendum and first experimental evidence on neutron supermirrors . In: Communications on Physics (London) . tape 2 , no. 2 , 1977, p. 41-43 .