Researchers examine black phosphorus’ potential for spintronics applications

Researchers at Newcastle University, National University of Singapore (NUS) and Japan's National Institute for Materials Science have reported a significant discovery in the field of spintronics based on the unique properties of an ultrathin, two-dimensional material called black phosphorus and how it transports spinning electrons.

Spintronics utilizes the intrinsic spin of electrons to create more energy-efficient devices. Electrons have a spin state of “up” or “down” causing the electrons to act like tiny magnets and manipulating this state has been seen by researchers as crucial for achieving lower power operation in electronic devices. This is because the spin motion of electrons inherently dissipates far less heat than the movement of electrical charge used in traditional electronics. Whilst the phenomenon of spin itself has been widely studied, the challenge has been finding a material with the optimal properties for creating the channels that transport spins.


“Choosing the right material is paramount in spintronics,” said Prof. Barbaros Özyilmaz from NUS. “Highly efficient and functional spin channel materials are the backbone of spintronics devices, allowing us to manipulate and control spins for diverse applications.”

Black phosphorus is a unique form of phosphorus with a distinct puckered or corrugated crystal structure. The researchers found that this property allows it to transport spinning electrons in a specific direction, making it quite different from other materials.

Dr. Ahmet Avsar explained: “The crystal structure of black phosphorus imparts directional characteristics to spin transport, offering new possibilities for controlling spintronics devices.”

To understand how the material behaves, the researchers created very thin spintronics devices using black phosphorus. They then studied how spinning electrons move in different directions by injecting them into the material and measuring the resulting signal. When they applied a strong magnetic field to the black phosphorus layer, the spinning electrons became much more noticeable, changing how they interacted with their surroundings and making them last at least six times longer.

“Our research also found that black phosphorus enables spinning behavior to be controlled electrically. We can achieve very long-distance spin diffusion or completely halt its diffusion by simply applying an electric field,”said Dr. Avsar. “This, along with its exceptional ability to direct spin transport, makes black phosphorus a special material for manipulating spins which is a major step forward in the world of spintronics.”

The research team is now exploring how this discovery can be applied to new spintronic devices that can be controlled in a more advanced way, not just by the basic spinning states but also by taking advantage of the unique spinning characteristics to direct the flow of spins.

They believe this could lead to exciting possibilities for low-power, highly functional electronic devices.

Posted: Feb 24,2024 by Roni Peleg