QuSpin Research - Center for Quantum Spintronics (QuSpin)
The principal goal of the center is to describe, characterize and develop recently identified quantum approaches to control electric signals in advanced nano electronics, conceptually different from those existing today.
It is our hypothesis that the waste of energy in conventional electronics can be circumvented by utilizing the dynamics of quantum entities other than the electron charge. The electron spin, the electron’s magnetic moment, is a prime example of a quantum entity.
QuSpin will develop new concepts for the utilization of spin and pseudo-spin quantum states in low-dissipation systems. Our aim is to control these states electrically in innovative nanostructured combinations of magnetic insulators, topological insulators, and superconductors.
The research focuses on three judiciously chosen low-dissipation systems: magnetic insulators, topological insulators, and superconductors which correspond to three research themes: insulator spintronics, topological matter, and super spintronics.
Our unique competitive edge is addressing the ultra-low power innovations by uniting expertise from insulator spintronics, topological matter, and super spintronics. While these themes are individually exciting, we combine them to generate significant added value.
Electrons can move in free air. In materials, their motion can differ significantly. In metals, the collective flow of the electrons resembles that of particles, but with dramatically altered properties. Their mass, charge, and even spin can be modified. This dressed behavior resembles new particles, so-called quasi-particles, that requires new models and new concepts. We will address how such quasi-particles can convey spin information with exceptional tiny energy losses.
Also, we will consider the dynamical evolution of the spin states for high-speed electronics. A supercurrent is a remarkable phenomenon where a current can flow in a supercurrent with no electrical resistance and no energy loss. New material combinations with such properties would revolutionize electronics and have a significant impact on society at large. We will consider how spin can flow via supercurrents.
Successfully meeting these challenges has the potential to transform electronic data transmission, storage, and processing. Ultimately, dissipationless spin transport would solve the problem of energy waste to the environment with potential uses in disruptive technologies.
Illustrations: Alexander Somma/NTNU
The electron spin, the electron’s magnetic moment, is a prime example of a quantum entity. Classically, when the earth orbits around the sun, it has an orbital angular momentum. The spin is the electron’s intrinsic angular momentum. It is as if something orbits around inside the electron. While such an analogue can be useful, it is not what really happens. Instead, the spin is an intrinsic property of the electron. Furthermore, in measurements, there are only two possible outcomes of the spin, clockwise rotation or counter- clockwise rotation. We denote these states as spin-up and spin-down.
Magnetic insulators are excellent conductors of spin while forbidding the energy-consuming process of charge transport. In magnetic insulators, the quanta of the spin vibrations can act as new low power dissipation information carriers.
Topological insulators allow ultra-low dissipation transport of charge and spin at the surface, but inhibit lossy processes in the bulk. An important aspect is the exceptional strong coupling between charge and spin signals.
Superconductors have exactly zero electrical resistance and expel magnetic fields. Cleverly designed nanostructured superconductors in combination with magnetic materials exhibit intriguing new electrical and magnetic phenomena coupling charge and spin signals.