A method for making an ordered magnetic alloy includes (a) providing a thermally conductive base having opposite first and second surfaces; (b) forming a thermal barrier layer on the first surface of the thermally conductive base; (c) forming a disordered magnetic alloy layer on the thermal barrier layer, the disordered magnetic alloy layer being made from a disordered alloy which contains a first metal selected from Fe, Co, and Ni, and a second metal selected from Pt and Pd; and (d) after step (c), applying a transient heat to the thermally conductive base to cause rapid thermal expansion of the thermally conductive base, which, in turn, causes generation of an in-plane tensile stress in the disordered magnetic alloy layer.

A method for making an ordered magnetic alloy includes (a) providing a thermally conductive base having opposite first and second surfaces; (b) forming a thermal barrier layer on the first surface of the thermally conductive base; (c) forming a disordered magnetic alloy layer on the thermal barrier layer, the disordered magnetic alloy layer being made from a disordered alloy which contains a first metal selected from Fe, Co, and Ni, and a second metal selected from Pt and Pd; and (d) after step (c), applying a transient heat to the thermally conductive base to cause rapid thermal expansion of the thermally conductive base, which, in turn, causes generation of an in-plane tensile stress in the disordered magnetic alloy layer.

Systems, methods, and apparatus for generating an ideal diamagnetic response are disclosed. A disclosed diamagnetic system includes a metal foil or a first substrate having at least one surface that is coated by a metallic layer (e.g., permalloy). The diamagnetic system also includes a second substrate having at least one surface that is coated by graphene. The first and second substrates are immersed in an alkane (e.g., n-heptane). The diamagnetic system produces a diamagnetic response at room temperature in an applied magnetic field when the alkane is added to surround the permalloy and graphene.

Systems, methods, and apparatus for generating an ideal diamagnetic response are disclosed. A disclosed diamagnetic system includes a metal foil or a first substrate having at least one surface that is coated by a metallic layer (e.g., permalloy). The diamagnetic system also includes a second substrate having at least one surface that is coated by graphene. The first and second substrates are immersed in an alkane (e.g., n-heptane). The diamagnetic system produces a diamagnetic response at room temperature in an applied magnetic field when the alkane is added to surround the permalloy and graphene.

A method for inducing tunable ferromagnetism with hydrogen annealing in delafossite films includes obtaining a PdCoO.sub.2 thin film, positioning the PdCoO2 thin film on a substrate, annealing the PdCoO.sub.2 thin film by hydrogenation, and cooling the PdCoO.sub.2 thin film to approximately room temperature.

A method for inducing tunable ferromagnetism with hydrogen annealing in delafossite films includes obtaining a PdCoO.sub.2 thin film, positioning the PdCoO2 thin film on a substrate, annealing the PdCoO.sub.2 thin film by hydrogenation, and cooling the PdCoO.sub.2 thin film to approximately room temperature.

A method of producing an oppositely magnetized magnetic structure within or on a substrate material includes: generating first and second numbers of cavities within or on a substrate material and filling the first and second numbers of cavities with first and second hard magnetic materials, respectively exhibiting first and second coercive field strengths, wherein the second coercive field strength is smaller than the first coercive field strength. The method further includes magnetizing, in a first direction, the first and second arrangements of magnetic structures, by a magnetic field having a field strength that exceeds the first and second coercive field strengths. The method further magnetizes the second arrangement of hard magnetic structures in a second direction, which differs from the first direction, by a second magnetic field having a field strength below the first coercive field strength but greater than the second coercive field strength.

A method of producing an oppositely magnetized magnetic structure within or on a substrate material includes: generating first and second numbers of cavities within or on a substrate material and filling the first and second numbers of cavities with first and second hard magnetic materials, respectively exhibiting first and second coercive field strengths, wherein the second coercive field strength is smaller than the first coercive field strength. The method further includes magnetizing, in a first direction, the first and second arrangements of magnetic structures, by a magnetic field having a field strength that exceeds the first and second coercive field strengths. The method further magnetizes the second arrangement of hard magnetic structures in a second direction, which differs from the first direction, by a second magnetic field having a field strength below the first coercive field strength but greater than the second coercive field strength.

A sintered R.sub.2M.sub.17 magnet is provided that comprises at least 70 Vol % of a Sm.sub.2M.sub.17 phase, wherein R is at least one of the group consisting of Ce, La, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm,

Yt, Lu and Y, and M comprises Co, Fe, Cu and Zr. In an area of the R.sub.2M.sub.17 sintered magnet of 200 by 200 μm viewed in a Kerr micrograph, an areal proportion of demagnetised regions after application of an internal opposing field of 1200 kA/m is less than 5% or less than 2%.

A sintered R.sub.2M.sub.17 magnet is provided that comprises at least 70 Vol % of a Sm.sub.2M.sub.17 phase, wherein R is at least one of the group consisting of Ce, La, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm,

Yt, Lu and Y, and M comprises Co, Fe, Cu and Zr. In an area of the R.sub.2M.sub.17 sintered magnet of 200 by 200 μm viewed in a Kerr micrograph, an areal proportion of demagnetised regions after application of an internal opposing field of 1200 kA/m is less than 5% or less than 2%.