Magnetic Properties of Low Temperature Phase MnBi of Island Structure
The magnetic and structural properties of island-structured LTP MnBi fabricated onto MgO single crystal substrates are discussed. The size and height of the “Volmer-Weber” type islands vary from place to place but are averagely a few microns and sub-microns, respectively. From the wetting angle (40 ∼ 60°) of those islands, the surface energy ΥMnBi of LTP MnBi is found to be 0.5∼0.8 J/m². Those MnBi islands possesses the magnetic anisotropy constant Kᵤ and saturation magnetization Mₛ close to those for bulk over a temperature range of 5 to 400 K. There seems to be a correlation between Ku and lattice constant c measured at 300K. The Kᵤ is found to be inversely proportional to Mₛ⁵ over the temperature range from 5 K to 400 K, as compared to the Mₛ⁸ dependence for those fabricated onto fused silica glass substrates.