Spin glasses: redux: an updated experimental/materials survey

Area of Science:

• Condensed Matter Physics
• Statistical Mechanics
• Materials Science

Background:

• The spin-glass field has been studied for over 40 years.
• Spin glasses (SG) are a key area in statistical mechanics, particularly concerning classical phase transitions.
• Understanding SG behavior is crucial for exploring strongly correlated materials.

Purpose of the Study:

• To review the spin-glass field from an experimental phenomenological viewpoint.
• To emphasize new spin glass materials and their relation to current problems in condensed matter physics.
• To explain the spin density wave (SDW) concept and its relation to SG.

Main Methods:

• Definition and basic ingredients of spin glasses.
• Characterization of canonical spin glass behavior through four experimental properties.
• Introduction to early theories and models, including the spin density wave (SDW) concept.

Main Results:

• Distinction between short-range SDW (SG) and long-range SDW (conventional magnetic transition).
• Overview of the current state of SG research, including simulations and proposals for chiral and quantum SGs.
• Identification of unconventional materials exhibiting SG-like freezing and glassy ground states.

Conclusions:

• Spin glasses exhibit unique properties relevant to various strongly correlated materials.
• New materials like superconductors and heavy fermions show spin-glass-like behavior.
• Future research directions include exploring quantum spin glasses and novel glassy states.