Strong Magnetocaloric Coupling in Oxyorthosilicate with Dense Gd3+ Spins
Ziyu W Yang1,2, Jie Zhang2,3, Dabiao Lu2,3
1College of Civil and Transportation Engineering, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Inorganic Chemistry
|March 21, 2023
Summary
Gadolinium oxyorthosilicate (Gd2SiO5) shows promise as a magnetic refrigerant material. It exhibits significant magnetic entropy change and adiabatic temperature change, making it suitable for 2-20 K cryocoolers.
Area of Science:
- Materials Science
- Thermodynamics
- Magnetism
Background:
- Developing effective refrigerant materials is crucial for advancing magnetic cooling technologies.
- Gadolinium oxyorthosilicate (Gd2SiO5) is explored as a potential candidate for magnetocaloric applications.
Purpose of the Study:
- To investigate the thermodynamic and magnetocaloric properties of Gd2SiO5.
- To assess its potential as a working material for magnetic refrigeration.
Main Methods:
- Field-dependent static magnetization measurements.
- Specific heat measurements.
- Mean-field estimation of correlation strength.
Main Results:
- Gd2SiO5 exhibits antiferromagnetic correlations between ferromagnetic Gd-Gd layers with a correlation strength of |J|S² ≈ 3.4 K.
- A magnetic entropy change of 0.40 J K⁻¹ cm⁻³ (58.5 J K⁻¹ kg⁻¹) at 2.7 K and an adiabatic temperature change of 23.2 K for a 8.9 T field change were observed.
- The ratio of magnetic to lattice entropy (Sm/SL) is 21.3 at 20 K.
Conclusions:
- Gd2SiO5 demonstrates significant magnetocaloric effects, particularly in the 2-20 K range.
- Its layered A-type spin arrangement enhances magnetocaloric coupling, suggesting potential for high-performance magnetic refrigerants.
- This material is a promising candidate for cryocoolers operating with Stirling and Carnot cycles.
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