A passive thermal switch device, for regulating a temperature of a thermal component configured to generate heat, includes a first plate and a second plate. The first plate is provided on the thermal component. The first plate includes a thermal switch material that switches from an antiferromagnetic state to a ferromagnetic state upon exceeding a state transition temperature. The second plate includes a permanent magnet. The second plate is moveable between a thermal insulator position and a thermal conductor position based on a temperature of the thermal switch material. In the thermal insulator position, the second plate is spaced apart from the first plate. In the thermal conductor position, the second plate is in contact with the first plate.

A tunnel magnetoresistance (TMR) sensing element includes a layer stack having a tantalum-nitride (TaN) layer; a reference layer system; a magnetic free layer having a magnetically free magnetization; and a tunnel barrier layer arranged between the reference layer system and the magnetic free layer. The reference layer system includes a pinned layer having a fixed pinned magnetization; a reference layer having a having a fixed reference magnetization; a coupling interlayer arranged between the pinned layer and the reference layer; and a natural antiferromagnetic (NAF) layer comprising iridium-manganese (IrMn), wherein the NAF layer is formed in direct contact with the TaN layer, wherein the NAF layer is configured to hold the fixed pinned magnetization in a first magnetic orientation and hold the fixed reference magnetization in a second magnetic orientation, and wherein the direct contact of the NAF layer with the TaN layer increases a blocking temperature of the NAF layer.

A magnetic plate may be provided by a device, comprising: a first magnet, a second magnet, and a third magnet; a plate defining: a first indentation in which the first magnet is disposed; a second indentation in which the second magnet is disposed; and a third indentation in which the third magnet is disposed; and a contact surface; and, a target area; wherein: the first indentation, the second indentation, and the third indentation are located on the plate relative to a target area of the plate so that a net magnetic field generated by the first magnet, second magnet, and third magnet has a field strength that is below a predefined threshold within the target area. A keying feature may be provided so as to prevent misalignment between the plate and a device to which it can be magnetically connected.

An optical sensor is disclosed. The optical sensor may include a substrate, a topological insulator layer formed on the substrate, an oxide layer formed on the topological insulator layer, a graphene layer stacked on the oxide layer, and a dielectric layer covering the graphene layer.

A permanent magnet including, at least once per group of ten consecutive ferromagnetic layers, a growth layer directly interposed between a top antiferromagnetic layer of a previous pattern and a bottom antiferromagnetic layer of a following pattern. This growth layer is entirely realized in a nonmagnetic material chosen from the group made up of the following metals: Ta, Cu, Ru, V, Mo, Hf, Mg, NiCr and NiFeCr, or it is realized by a stack of several sublayers of nonmagnetic material disposed immediately on one another, at least one of these sublayers being entirely realized in a material chosen from the group. The thickness of the growth layer is greater than 0.5 nm.

A magnetoresistive element for a magnetic sensor, the magnetoresistive element including a tunnel barrier layer between a reference layer having a fixed reference magnetization and a sense layer having a free sense magnetization, wherein the sense magnetization includes a stable vortex configuration. The magnetoresistive element further includes a reference pinning layer in contact with the reference layer and pining the reference magnetization by exchange-bias at a first blocking temperature. The magnetoresistive element further includes a sense pinning layer in contact with the sense layer and pining the sense magnetization by exchange-bias at a second blocking temperature lower that the first blocking temperature. Additionally, a method for manufacturing the magnetoresistive element.

A tunnel magnetoresistance (TMR) sensing element includes a layer stack having a tantalum-nitride (TaN) layer; a reference layer system; a magnetic free layer having a magnetically free magnetization; and a tunnel barrier layer arranged between the reference layer system and the magnetic free layer. The reference layer system includes a pinned layer having a fixed pinned magnetization; a reference layer having a having a fixed reference magnetization; a coupling interlayer arranged between the pinned layer and the reference layer; and a natural antiferromagnetic (NAF) layer comprising iridium-manganese (IrMn), wherein the NAF layer is formed in direct contact with the TaN layer, wherein the NAF layer is configured to hold the fixed pinned magnetization in a first magnetic orientation and hold the fixed reference magnetization in a second magnetic orientation, and wherein the direct contact of the NAF layer with the TaN layer increases a blocking temperature of the NAF layer.

A method provides a read sensor stack including an antiferromagnetic (AFM) layer, a pinned layer on the AFM layer, a free layer, and a nonmagnetic layer between the free and pinned layers. Providing the AFM layer includes depositing an AFM layer first portion at a first elevated temperature and at a rate of at least 0.1 Angstrom/second. This AFM layer first portion is annealed in-situ at at least one hundred degrees Celsius. An AFM sublayer is deposited at an elevated temperature and at a sublayer deposition rate of less than 0.1 Angstrom/second. The already-deposited portion of the AFM layer is annealed in-situ at at least one hundred degrees Celsius and less than five hundred degrees Celsius. The sublayer depositing and annealing steps may be repeated in order at least once to provide an AFM layer second portion that has multiple sublayers and is thinner than the AFM layer first portion.

Provided herein are systems, methods, and compositions for magnetic nanoparticles and bulk nanocomposite magnets.

Provided herein are systems, methods, and compositions for magnetic nanoparticles and bulk nanocomposite magnets.