Magnetism

An international researchers team recently found that a new 'double perovskite' material could become a more environmentally friendly platform for spintronics devices thanks to its lead-free nature. While the material in its current form is only magnetic below 30 K ' too low for practical applications ' developers at Linköping University in Sweden, together with colleagues in the US, the Czech Republic, Japan, Australia and China, say that their preliminary experiments are a promising step towards making rapid and energy-efficient information storage devices from this novel optoelectronic material.

Recently, researchers discovered that lead halide perovskites display interesting spin properties thanks to lead's strong spin-orbit coupling. This coupling links the motion of an electron to its quantum spin, and its strength determines how much the intrinsic spin of an electron will interact with the magnetic field induced as the electron moves through the material. Such a coupling is therefore important not only for the magnetic properties of a material, but also for the performance of any spintronics devices.

Researchers at Linköping University in Sweden have announced the development of an optoelectronic magnetic double perovskite. The discovery could open the door to combining spintronics with optoelectronics for rapid and energy-efficient information storage.

The team explains that one type of perovskite that contains halogens and lead has recently been shown to have interesting magnetic properties, opening the possibility of using it in spintronics. Spintronics is thought to have huge potential for the next generation of information technology, since information can be transmitted at higher speeds and with low energy consumption. However, magnetic properties of halide perovskites have until now been associated only with lead-containing perovskites, which has limited the development of the material for both health and environmental reasons.

Physicists at the École polytechnique fédérale de Lausanne (EPFL) in Switzerland have used perovskite materials to alter a magnetic bit's polarity with light, potentially opening the door to denser and faster disk drives using magneto-optical technology.

Researchers László Forró, Bálint Náfrádi, Péter Szirmai and Endre Horváth suggest magneto-optical drives using this method could be physically smaller, faster and cheaper than today's disk drives. They also say it is an alternative to heat-assisted magnetic recording (HAMR).

Researchers at Cornell used theoretical techniques to predict that using intense mid-infrared laser light on a titanium perovskite can dynamically induce a magnetic phase transition ' taking the material from its ferromagnetic ground state to a hidden anti-ferromagnetic phase. This dramatic shift could have useful applications, particularly in optical information processing.

'It would be a kind of optical switch,' the researchers said. 'You have a material where it's magnetic and 'non-magnetic.' It's going between those two states with light'.

EPFL scientists have developed a new perovskite material whose magnetic order can be rapidly changed without disrupting it due to heating. This novel material may potentially be used to build next-generation hard drives.

The EPFL team synthesized a ferromagnetic photovoltaic material. This material is a modified version of perovskite, that exhibits unique properties that make it particularly interesting as a material to build next-generation digital storage systems. The researchers explain that they have basically created the first magnetic photoconductor; This new crystal structure combines the advantages of both ferromagnets, whose magnetic moments are aligned in a well-defined order, and photoconductors, where light illumination generates high density free conduction electrons.