SwissNeutronics provides advanced spin-selectors for neutron polarization, featuring RF spin flippers with no beam obstruction and polarizing cavities achieving ~99% polarization and ~35% transmission. Cavity configurations include serial and parallel V setups, with thin Si wafers and simulation tools (McStas) supporting precise system modeling and optimization for scientific applications.

SwissNeutronics offers state-of-the-art spin selectors designed for high neutron polarization and manipulation in ...

SwissNeutronics offers state-of-the-art spin-selectors designed for high neutron polarization and manipulation in scientific research. Our RF spin flippers are engineered to operate across a broad wavelength range of 2–20 Å, ensuring versatility in experimental setups. A key advantage is the absence of material in the beam path, preserving neutron beam intensity. These devices utilize a gradient magnetic field and an RF field tuned to approximately 100–150 kHz, with all necessary electronics provided for seamless integration.

Complementing the spin flippers, SwissNeutronics‘ polarizing cavities deliver exceptional performance. With polarization levels reaching approximately 99% and transmission efficiencies around 35%, they are ideal for high-precision applications. Configurations include serial arrangements (double or triple V) for enhanced polarization and parallel multi-channel setups to optimize throughput. Design features such as overlapping Si wafer at the tip and side intrusion help avoid streaming of neutrons with the wrong spin-state. The use of ultra-thin silicon wafers (0.3 mm) further boosts transmission rates.

To support customization and optimization, SwissNeutronics provides access to sophisticated simulation tools (components for the software package McStas), enabling researchers to model and refine their neutron optics systems with high accuracy.

Technical Highlights

RF Spin Flipper

  • Broad Wavelength Range: Operates typically between 2 – 20 Å.
  • Beam Integrity: No material introduced into the neutron beam path.
  • Magnetic Field Design: Utilizes a gradient magnetic field for efficient spin manipulation.
  • RF Field Specifications:
    – Frequency: ≈ 100 – 150 kHz
    – Stable and precise RF control for reliable flipping performance.
  • Integrated Electronics: Complete electronic control system provided for ease of operation.

Polarizing Cavities

  • High Polarization Efficiency: Achieves polarization levels of P ≈ 99%.
  • Transmission Performance:
    Ratio: T = Φpolarized,out/Φunpolarized,in ≅ 35%
  • Configurable Arrangements:
    – Serial (double or triple V) for maximum polarization.
    – Parallel (multi-channel) for increased throughput.
  • Optimized Neutron Spin Filtering:
    Prevents streaming of “up” neutrons through careful design:
    – Overlap at tips
    – Intrusions at sides
  • High Transmission Materials:
    Thin Si wafers (t = 0.3 mm) ensure minimal attenuation.
  • Advanced Simulation Support:
    Compatible with McStas for detailed modeling and optimization.
Imaging beamline @ CARR

Spin-selector (multi-channel V-cavity + RF spinflpper)

MR beamline @ CSNS

Spin-selector (ZZ-cavity + RF spin flipper)