Related technologies

While the field of spintronics tries to leverage the spin angular momentum of electrons to develop new technologies, these particles' orbital momentum has so far been rarely considered. Currently, generating an orbital current (i.e., a flow of orbital angular momentum) remains far more challenging than generating a spin current. Nonetheless, approaches to successfully leveraging the orbital angular momentum of electrons could open the possibility for the development of a new class of devices called orbitronics.

Researchers at Japan's Keio University and Germany's Johannes Gutenberg University have reported the successful generation of an orbital current from magnetization dynamics, a phenomenon called orbital pumping. Their outlines a promising approach that could allow engineers to develop new technologies leveraging the orbital angular momentum of electrons.

Researchers from National Renewable Energy Laboratory (NREL), University of Utah, Université de Lorraine CNRS and University of Colorado Boulder have improved upon their previous work, that included incorporating a perovskite layer that allowed the creation of a new type of polarized light-emitting diode (LED) that emits spin-controlled photons at room temperature without the use of magnetic fields or ferromagnetic contacts. In their latest work, they have gone a step further by integrating a III-V semiconductor optoelectronic structure with a chiral halide perovskite semiconductor.

The team transformed an existing commercialized LED into one that also controls the spin of electrons. The results could provide a pathway toward transforming modern optoelectronics, a field that relies on the control of light and encompasses LEDs, solar cells, and telecommunications lasers, among other devices.

Researchers at the University of Wyoming, Pennsylvania State University, Northeastern University, The University of Texas at Austin, Colorado State University and Japan's National Institute for Materials Science have developed a method to control tiny magnetic states within ultrathin, two-dimensional van der Waals magnets - a process similar to how flipping a light switch controls a bulb.

The team developed a device known as a magnetic tunnel junction, which uses chromium triiodide - a 2D insulating magnet only a few atoms thick - sandwiched between two layers of graphene. By sending a tiny electric current called a tunneling current through this sandwich, the direction of the magnet's orientation of the magnetic domains (around 100 nanometers in size) can be dictated within the individual chromium triiodide layers.

Researchers at Japan's RIKEN have conducted an experiment that could help the development of new energy-efficient spintronics devices. They used heat and magnetic fields to create transformations between spin textures—magnetic vortices and antivortices known as skyrmions and antiskyrmions—in a single crystal thin plate device. What's even more important is that they achieved this at room temperature.

Skyrmions and antiskyrmions, which are textures that exist within special magnetic materials involving the spin of the electrons in the material, are an active area of research, as they could be used for next-generation memory devices, for example, with skyrmions acting as a "1" bit and antiskyrmions a "0" bit. In the past, scientists have been able to move them in a variety of ways, and to create transformations between them using electric current. However, because current electronic devices consume electrical power and produce waste heat, the researchers in the group, led by Xiuzhen Yu at the RIKEN Center for Emergent Matter Science, decided to see if they could find a way to create the transformations using heat gradients.

Scientists at Delft University of Technology have used superconducting diamagnetism to shape the magnetic environment governing the transport of spin waves—collective spin excitations in magnets that are promising on-chip signal carriers—in a thin-film magnet. 

The team has shown that it’s possible to control and manipulate spin waves on a chip using superconductors for the first time. These tiny waves in magnets may offer an alternative to electronics in the future, interesting for energy-efficient information technology or connecting pieces in a quantum computer, for example. The results of this work give scientists new insight into the interaction between magnets and superconductors.

Scientists at Cornell University, Washington University in St. Louis and University of Maryland have revealed a new phase of matter in candidate topological superconductors that could have significant consequences for condensed matter physics and for the field of quantum computing and spintronics.

The researchers discovered and visualized a crystalline yet superconducting state in a new and unusual superconductor, Uranium Ditelluride (UTe₂), using one of the world’s most powerful millikelvin Scanned Josephson Tunnelling Microscopes (SJTM). This “spin-triplet electron-pair crystal” is a previously unknown state of topological quantum matter.

Researchers from Cambridge University in the UK, Korea's DGIST and Harvard University in the U.S have shown that electron spins could become more efficient and easier to manage through a light-based approach using halide perovskite semiconductors. The team observed ultrafast spin-domain formation in polycrystalline halide perovskite thin films in response to irradiating the films with circularly polarized light at room temperature.

Photoinduced spin-charge interconversion in semiconductors, with spin-orbit coupling, could provide a route to spintronics that does not require external magnetic fields, which tend to be challenging to control. An electron can have two spin states, up or down, and these states can be used to store and process information. But manipulating spin states can be tricky, requiring the use of magnetic fields on perfectly ordered materials at extremely low temperatures to work.

Researchers from Oak Ridge National Laboratory (ORNL) have proposed a mechanism to control the magnetic properties of topological quantum material (TQM) by using magnetoelectric coupling: a mechanism that uses a heterostructure of TQM with two-dimensional (2D) ferroelectric material, which can dynamically control the magnetic order by changing the polarization of the ferroelectric material and induce possible topological phase transitions. 

The novel concept was demonstrated using the example of the bilayer MnBi₂Te₄ on ferroelectric In₂Se₃ or In₂Te₃, where the polarization direction of the 2D ferroelectrics determines the interfacial band alignment and consequently the direction of the charge transfer. This charge transfer, in turn, enhances the stability of the ferromagnetic state of MnBi₂Te₄ and leads to a possible topological phase transition between the quantum anomalous Hall (QAH) effect and the zero plateau QAH.

Researchers from the Hebrew University of Jerusalem in Israel have made a recent discovery that could change the face of spintronics research.

A spintronics device developed by Professor Capua's lab

They discovered that the most important equation used to describe magnetization dynamics, namely the Landau-Lifshitz-Gilbert (LLG) equation, also applies to the optical domain. Consequently, they found that the helicity-dependent optical control of the magnetization state emerges naturally from their calculations. This is a very surprising result since the LLG equation was considered to describe much slower dynamics and it was not expected to yield a meaningful outcome also at the optical limit.

A new instrument called ALICE II is available at BESSY II, that allows magnetic X-ray scattering in reciprocal space using a new large area detector. Recntly, researchers from HZB and Technical University Munich demonstrated the performance of ALICE II by analyzing helical and conical magnetic states of an archetypal single crystal skyrmion host.

The new instrument was conceived and constructed by HZB physicist Dr. Florin Radu and the technical design department at HZB in close cooperation with Prof. Christian Back from the Technical University Munich and his technical support. It is now available for guest users at BESSY II as well.