Single-Atom Magnets on Thermally Stable Adsorption Sites: Dy on NaCl(100)

Area of Science:

• Solid State Physics
• Materials Science
• Quantum Magnetism

Background:

• Single-atom magnets (SAMs) are crucial for next-generation data storage.
• Developing SAMs with high thermal stability and long spin lifetimes is a key challenge.
• Dysprosium (Dy) is a promising element for creating magnetic properties at the atomic scale.

Purpose of the Study:

• To investigate the magnetic properties of individual Dysprosium atoms adsorbed on NaCl(100) thin films.
• To determine the feasibility of using NaCl as a substrate for stable single-atom magnets.
• To explore the influence of adsorption sites on the magnetic behavior of Dy atoms.

Main Methods:

• Epitaxial growth of NaCl(100) thin films.
• Deposition of individual Dysprosium atoms onto the NaCl surface.
• Characterization using techniques sensitive to atomic structure and magnetic properties (e.g., scanning tunneling microscopy, magnetic measurements).
• Analysis of electronic configuration (4f occupancy) and magnetic relaxation times (T1).

Main Results:

• Individual Dy atoms substituting Na on NaCl(100) show thermal stability up to 300 K.
• These Dy atoms exhibit out-of-plane magnetization and a spin relaxation time (T1) of ~10 s at 2.5 K.
• Dy atoms adsorbed on Cl and bridge sites display different electronic configurations (4f10) and magnetic hysteresis.
• Long magnetic relaxation times (T1 = 550 s at 0.3 T and 2.5 K) were observed for Dy on top-Cl sites.

Conclusions:

• NaCl(100) serves as an effective platform for realizing stable single-atom magnets.
• Dysprosium atoms on NaCl exhibit promising magnetic bistability and long spin relaxation times.
• The findings open avenues for designing robust atomic-scale magnetic devices.