Domestic researchers have developed a new nano structure that can freely control the direction of electrons without external magnetic fields or cryogenic devices. It has been evaluated that this could lead to the development of next-generation memory that consumes less power and is faster than existing electronic devices, thereby reducing heat generation in smartphones and large-scale data centers.
A joint research team from Korea University and Seoul National University noted, "We created a three-dimensional structure of a spiral that twists like a spring and confirmed that the current and voltage signals change depending on the direction of the spiral," in a paper published on the 5th in the international journal Science.
An electron is a negatively charged particle that orbits around the atomic nucleus. It carries an electric charge and possesses a special property called spin. In quantum mechanics, which explains the physical phenomena of the microscopic world, spin refers to the intrinsic angular momentum of a particle, and contrary to the term, it is unrelated to the particle's rotation. Due to spin, physical phenomena such as magnetism occur, allowing it to be viewed as a tiny magnet at the atomic level.
The charge of an electron is represented as positive (+) and negative (-), and spin is indicated as up (↑) or down (↓), like a compass needle. Electronic devices represent the presence or absence of electrons as 1 or 0, utilizing only charge up to now to store and process information. By also using spin (↑, ↓), information can remain intact even when power is cut off, allowing for the creation of semiconductors that operate much faster with significantly less power. It represents a next-generation semiconductor technology that is smarter, faster, and consumes less electricity.
Until now, it has been impossible to change the direction of an electron's spin as desired. Proper control of spin was only achievable under extremely strong magnetic fields or at cryogenic temperatures of several hundred degrees Celsius below zero, making practical application in devices challenging.
This research overcame such limitations. The researchers discovered that the direction in which a nano-sized spiral is twisted changes the electron's spin. This enables easier and more efficient control of the electron's spin. Professor Kim Young-geun from the Department of New Material Engineering at Korea University, who led the research, stated, "Magnetic materials have the ability to self-align the spin of electrons, so by using a spiral structure, we can control the flow of electrons as desired."
Co-author Professor Nam Ki-tae from the Department of Materials Science and Engineering at Seoul National University explained, "Unlike organic materials, controlling the twisting direction of nanostructures at the nanoscale in metals was a very difficult problem," adding, "This research is the first to accurately control whether the spiral twists to the right or to the left using molecules."
References
Science (2025), DOI: www.doi.org/10.1126/science.adx5963