BT9 MACS

Instrument Purpose

To deliver unprecedented sensitivity and speed for mapping dynamic correlations in condensed matter, specifically designed to detect the faint signatures of quantum fluctuations and magnetic excitations.

The NCNR Advantage

• Unrivaled Throughput: MACS provides two order-of-magnitude increase in detection efficiency compared to traditional triple-axis spectrometers by employing 20 independent spectroscopic channels that measure multiple scattering angles simultaneously.
• World-Record Cold Flux: Utilizing a massive, doubly-focusing PG monochromator (1428 cm²), MACS delivers one of the most intense monochromatic cold neutron beams in the world—up to 5 x 10⁸ n/cm²/s.
• Dynamic Resolution Control: Unique instrumentation allows for the near-independent tuning of energy and momentum (Q) resolution, giving researchers the flexibility to "zoom in" on specific quantum phenomena or "zoom out" for broad surveys of reciprocal space.

Research Domains

• Quantum Magnetism: The premier tool for the search for Quantum Spin Liquids and topological excitations.
• Unconventional Superconductivity: Probing the spin-fluctuation in heavy-fermion and high-T_c superconductors.
• Phase Transitions: Rapidly mapping diffuse scattering and critical fluctuations across wide ranges of temperature and pressure.
• Soft Matter Dynamics: Investigating molecular rotations and diffusion in complex liquids and polymers.

What You Can Measure

• Full (Q, E) Maps: Rapidly surveying the entire excitation spectrum of a material in a single experiment.
• Small Sample Dynamics: The high flux enables the measurement of microscopic single crystals (sub-10 mg) that were previously considered "too small" for neutron spectroscopy.
• Spin-Polarized Excitation Spectrum: Using ³He spin filters to differentiate between magnetic and structural (phonon) signals.
• Time-Resolved Inelastic Neutron Scattering: Adding another degree of freedom, time, to the neutron spectroscopy by employing time stamping to the measurement.