Magnetic and structural properties of EuS for magnetic tunnel junction barriers

In view of potential applications as a spin filter in spintronic devices, we systematically studied the growth by sputtering of ferromagnetic EuS barriers. The relationship between growth and magnetic and transport properties, also in combination with magnetic and nonmagnetic materials, was investigated. We demonstrate that growth at lower substrate temperatures (200 °C), followed by an anneal step at elevated temperatures (430 °C), leads to improved magnetic and transport properties of the barrier layer. We tentatively attribute the observed low-temperature magnetoresistance of high-resistive Al/PbS/EuS/PbS/Gd devices to spin filtering.In view of potential applications as a spin filter in spintronic devices, we systematically studied the growth by sputtering of ferromagnetic EuS barriers. The relationship between growth and magnetic and transport properties, also in combination with magnetic and nonmagnetic materials, was investigated. We demonstrate that growth at lower substrate temperatures (200 °C), followed by an anneal step at elevated temperatures (430 °C), leads to improved magnetic and transport properties of the barrier layer. We tentatively attribute the observed low-temperature magnetoresistance of high-resistive Al/PbS/EuS/PbS/Gd devices to spin filtering.

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