In situ electromagnet with active cooling for real-time magneto-optic Kerr effect spectroscopy

Area of Science:

• Materials Science
• Condensed Matter Physics
• Surface Science

Background:

• Achieving stable, homogeneous magnetic fields in ultrahigh vacuum (UHV) is critical for in situ thin film deposition.
• Existing setups often face thermal stability limitations, hindering real-time magnetic characterization.
• Magneto-optic Kerr effect (MOKE) spectroscopy is a powerful tool for studying magnetic properties of thin films.

Purpose of the Study:

• To design and implement a compact in situ electromagnet with active cooling for UHV environments.
• To integrate this electromagnet into a reflectance difference magneto-optic Kerr effect (RD-MOKE) spectroscopy system.
• To demonstrate its capability for real-time investigation of magnetic thin film growth.

Main Methods:

• Development of a compact electromagnet with an integrated active cooling system.
• Integration into a reflectance difference magneto-optic Kerr effect (RD-MOKE) spectroscopy setup for polar MOKE geometry.
• Real-time in situ deposition experiments of ultra-thin Ni films on Cu(110)-(2 × 1)O surfaces.

Main Results:

• The active cooling system enhanced thermal stability and allowed for higher electric currents, generating homogeneous magnetic fields.
• The integrated RD-MOKE system enabled synchronous measurement of optical anisotropy and magneto-optic response.
• A sharp spin reorientation transition was observed in real-time during Ni film deposition at a critical coverage of 9 monolayers.

Conclusions:

• The developed electromagnet and RD-MOKE system provide a robust platform for in situ, real-time studies of magnetic thin films.
• This setup facilitates detailed investigations of magnetic phase transitions and interfacial phenomena during film growth.
• It holds significant potential for advancing research in magnetic materials and spintronics.