Pushing the boundaries of light compression: Innovative nanostructures prolong the operational duration of terahertz gadgets

In a groundbreaking development, a team of international researchers has made a significant stride towards the creation of tunable THz optical devices with improved energy efficiency and enhanced performance. This discovery, published in the journal Light Science & Applications, could potentially transform various industries, including wireless communication systems, medical imaging, solar cells, and quantum information processing.

The THz band, often referred to as the last frontier in photonics, has the potential to enable lightning-fast wireless communications, sharper medical scans, and advanced security imaging. The research, led by scientists from institutions like the University of California, Berkeley, and the University of Texas at Austin, including groups led by Federico Capasso and other collaborators, aims to harness Dirac plasmon polaritons (DPPs) to control light in the terahertz (THz) frequency range, a largely untapped part of the spectrum.

The researchers designed the material in the form of laterally coupled nanostructures, also known as metaelements. They used topological insulator metamaterials, specifically epitaxial BiSe, in their study. Topological insulators have unusual properties, such as their interiors not conducting electricity but their surfaces doing so, allowing electrons to behave as if they have no mass.

The team was able to squeeze light into a space hundreds of times smaller than its natural wavelength using DPPs. By fine-tuning the spacing between these metaelements, they managed to increase the polariton wavevector by up to 20 percent and extend the attenuation length by more than 50 percent. This addresses the problem of high momentum and rapid energy loss that has kept DPPs from being practical in real-world devices.

The researchers were also able to tune the DPPs and control their behavior through geometry rather than brute force. This is a significant departure from previous methods, which required high-energy input to manipulate DPPs. The new approach could potentially lead to the development of more energy-efficient devices.

DPPs blend light with the motion of electrons in special ultra-thin materials. By controlling DPPs, the researchers hope to revolutionise how we send information, sense our environment, and build the next generation of quantum devices. The discoveries made in this study could be the foundation for a new generation of photonic technologies, including tunable and energy-efficient THz devices.

The study represents a significant step towards the development of practical, energy-efficient THz devices that could transform various industries. The potential applications of this technology are vast and exciting, and further research is needed to fully realise its potential.

Pushing the boundaries of light compression: Innovative nanostructures prolong the operational duration of terahertz gadgets