Condensed Matter & Thermal Physics Group, MPA-10

Neutron Scattering

Wei Bao - team leader

Neutron scattering is a powerful probe of structure and collective modes of condensed matter. We are focused on direct measurement of the energy and momentum-dependent dynamic magnetic correlation function, which completely determine magnetism of a material within linear response. Such experimental investigation is indispensable in frontier research of condensed matter physics where magnetism plays a role and theoretical understanding is incomplete. We are presently occupied with three topics which often concur in a sample:

1) Strongly correlated electrons in the Kondo lattice model and the Mott-Hubbard model, as exemplified in heavy-fermion materials, high-Tc cuprates and related magnetic oxides.

2) Quantum spin states and quantum phase transitions in low-dimensional and frustrated spin systems.

3) Spin-glass phenomenon, in particular, in quasi-low-dimensional materials.

To access the phase of interest, extreme sample environments such as temperature down to 40mK, magnetic field up to 14T, and pressure as high as 2GPa have been used during neutron scattering experiments. Success relies on close collaboration within the group and with outside collaborators in sample preparation, bulk characterization, neutron scattering and theoretical interpretation.

MPA-10 TEAMS

Thermal Physics

• Thermoacoustics
• Nonlinear Dynamics
• Advanced Fuel Cycle Initiative R&D

Correlated Electrons

• Materials Synthesis and Characterization
• Transport and Thermodynamics
• Novel Materials at Extreme Conditions
• Very Low Temperature Physics

Actinide Chemistry

• Heavy-Element Chemistry

Low Energy Spectroscopy

• Condensed Matter NMR
• Photoelectron Spectroscopy
• Magnetic Resonance Force Microscopy
• Mossbauer Spectroscopy
• Neutron Scattering