pseudospinvalve

A pseudospin valve is a magnetoresistive device that exhibits a significant change in electrical resistance when a magnetic field is applied. Unlike traditional spin valves, which rely on the relative orientation of magnetization in two ferromagnetic layers separated by a non-magnetic spacer, pseudospin valves utilize the spin-dependent scattering of conduction electrons in a single ferromagnetic layer. This scattering is influenced by the direction of electron spin relative to the magnetization direction of the ferromagnet.

The core principle behind a pseudospin valve involves a ferromagnetic material that exhibits a strong spin-orbit coupling. This coupling causes the scattering cross-section for electrons to depend on their spin orientation. When an external magnetic field is applied, it can alter the effective spin polarization of the conduction electrons or influence the magnetic domain structure within the ferromagnetic layer. This change then leads to a modulation of the electron scattering, resulting in a measurable change in the device's resistance.

Pseudospin valves can be fabricated using materials like iron or nickel alloys. Their resistance change is typically smaller than that observed in giant magnetoresistance (GMR) or tunneling magnetoresistance (TMR) devices. However, they offer potential advantages in terms of simpler fabrication and potentially lower power consumption. Research in this area focuses on enhancing the magnetoresistance ratio and exploring new material combinations to improve performance for applications in magnetic sensors and data storage.