Details

Autor(en) / Beteiligte

• Kim, Namkyu
• Han, Hee-Sung
• Lee, Sooseok
• Kim, Min-Ji
• Jung, Dae-Han
• Kang, Myeonghawn
• Ok, Hyejin
• Son, Youngkyun
• Lee, Sukbin
• Lee, Ki-Suk

Titel

Geometric effects in cylindrical core/shell hard–soft exchange-coupled magnetic nanostructures

Ist Teil von

• Journal of magnetism and magnetic materials, 2021-04, Vol.523, p.167599, Article 167599

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •Exchange-coupled nanostructured magnets for practical bulk magnets.•Exchange hardening should overcome shape anisotropy at the optimal aspect ratio.•Maximizing practical energy product considering demagnetizing field.•Maintaining the nucleation field positive for high energy product.•High energy product of the bulk system can be attained by using needle-shaped units. We explore the optimal condition for cylindrical core/shell hard-soft exchange-coupled magnetic nanostructures by obtaining full hysteresis loops for various geometries by obtaining full hysteresis loops for various geometrical variables, including the dimensional scale and soft/hard-magnetic phase volume ratio through micromagnetic simulations. For achieving maximum energy product (BH), it is essential to increase the demagnetizing field by increasing the volume fraction of the soft magnet while maintaining a positive nucleation field and, which can be possible by the scaling-down. To scale up the nanostructure to a bulk magnet having high BH can be achieved by forming an array of needle-shaped exchange-coupled cylinders. These findings could lead to the flexible design and scalable fabrication of exchange-coupled permanent magnets.