Korean Researchers Developed the World’s Smallest High-Performance ‘Nano Laser’


A domestic research team succeeded in developing the world’s smallest and high-efficient ultracompact nanolaser.
The control of light properties is highly regarded research topic in the field of advanced science. Controlling the angular momentum of light can be applied to various fields such as high-capacity optical communication and quantum information communication.

The Ministry of Science and ICT (MSIT) announced that a research team led by Professor Park Hong-Gyu of the Department of Physics and Astronomy at Seoul National University, in collaboration with Professor Yuri Kivshar’s team at the Australian National University, has successfully developed the world’s smallest, high-efficiency, high-performance nanolaser. This achievement was published in the international academic journal ‘Nature Photonics’ on the 27th (local time).

Previously, lasers that combined filters and laser devices were as large as tens of micrometers (µm) or more and had low performance. While ultra-small laser devices could operate with low energy, there had been no successful cases of incorporating the characteristic of angular momentum into the light of an ultra-small laser device.

Calculating and controlling the angular momentum of light is essential for laser development. When using light with different angular momenta for communication, it increases the amount of data transmitted simultaneously, enabling high-capacity optical communication.
The research team developed a photonic cavity, a device that traps light needed to realize laser light. Notably, they developed a ‘photonic disclination cavity,’ where air holes replaced atoms in an artificial crystal structure. Inspired by the similarity between electronic and photonic calculations in condensed matter physics and optics, the team utilized disclinations that refer to disturbances in the atomic arrangement within a crystal.

Using the photonic crystal cavity fabricated, the research team observed laser light exhibiting swirling patterns with various orbital angular momenta rotating in both clockwise and counterclockwise directions. This swirling laser light, known as a vortex laser, was confirmed to be generated for the first time through the photonic disclination cavity, marking a breakthrough in creating ultra-compact light sources.

This photonic cavity is 3.75 times smaller than those previously reported in academia, while the efficiency of the laser has increased by 24 times. Even with its reduced size, structural defects did not lead to any loss or distortion of light.
Professor Park emphasized the significance of developing a new laser structure called the disclination cavity and introducing the first-ever miniature vortex nano-laser. He stated, “The introduction of this new nano-laser is significant as it allows for precise control over polarization characteristics, which is expected to greatly contribute to the research of novel integrated photon and quantum circuits.”