RASHBA SPLITTING (Syllabus: GS Paper 3 - Sci & Tech)

Context: Using some 2-D carbides or nitrides of transition metals, a team of scientists have computationally designed a new composite quantum material that exhibits an exotic quantum property called Rashba splitting, in colossal scale, in a metallic environment.

Key Points

• Scientist focused their computational research on 2-D quantum materials, which are materials with confined geometry in one of the directions. 2-D materials are important as they are easier to assimilate in devices.
• This material can help interfacing with other substrates (2D substrates like graphene) in spintronic devices like spin transistors, spin diodes, and spin filters that take advantage of electron spin, a quantum property of electrons, to achieve higher performance.
• The team focused on creating composite 2-D quantum materials, which are quantum materials exhibiting two apparently different quantum properties, but connected by the basic requirement of symmetries. 
• In their study, by proper choice of materials ingredients, the workers managed to demonstrate the existence of two distinct quantum phenomena, - Rashba effect, (a momentum-dependent splitting of spin bands) and nonlinear anomalous Hall effect, arising from anomalous velocity of the electrons, in the same 2-D material.
• With the 2D composite material designed computationally, the scientists hope that the challenges of manufacturing Janus MXenes in the lab and at a large scale will be gradually overcome to bring benefits for devices, energy security, and the economy.