The arrival of the terahertz beam at the experimental station of the Tatu beamline at Sirius marks the beginning of its commissioning phase. Tatu is part of a package of ten new beamlines planned for Sirius Phase 2. It is the first beamline in the world specifically designed to operate in the terahertz range at a fourth-generation synchrotron light source.

A new window into the study of matter

The Tatu beamline was designed to explore the terahertz region of the electromagnetic spectrum, a frequency range associated with low-energy excitations that remains largely inaccessible through experimental techniques. In this region, researchers can investigate phenomena ranging from vibrations of heavier molecules to rotational modes and collective excitations in materials, enabling studies that cannot be performed using higher-energy radiation. 

One of Tatu’s main distinguishing features is the combination of terahertz radiation with nano-spectroscopy techniques. Using an atomic force microscopy (AFM) probe-based method, the radiation is confined to volumes on the order of tens of nanometers, making it possible to analyze structures far smaller than the wavelength of the radiation itself. “We are able to produce a probe just a few nanometers wide and study objects that are much smaller than the wavelength of the radiation,” explains Raul Freitas, coordinator of the Imbuia and Tatu beamlines. 

Connection between the Sirius Storage Ring and the Tatu beamline. (Credit: CNPEM)

This capability opens new opportunities for investigating quantum materials, including superconductors and topological insulators, as well as nanophotonic systems and a wide range of two-dimensional materials. It also holds potential for applications in fields such as telecommunications and data processing, particularly in the development of devices that use light, rather than electrons, to transmit information. 

Beyond materials science, Tatu will also contribute to research on biological systems. The terahertz range provides access to fundamental information about the structure of biomolecules, expanding the set of tools available for studies in the life sciences. 

The first Phase 2 beamline at Sirius

Tatu is one of ten new beamlines planned for Sirius Phase 2, an expansion effort aimed at significantly broadening the facility’s experimental capabilities. This package also includes three beamlines that will be part of the Orion project, dedicated to advanced research on pathogens. These new experimental stations are driving the development and adoption of techniques that have so far seen limited use worldwide, strengthening Brazil’s position in emerging areas of scientific research.

Interior of the Tatu beamline. (Credit: CNPEM)

Beginning of the commissioning phase

With the recent observation of the terahertz beam at the experimental station, the Tatu beamline has now entered its technical and scientific commissioning phase. This stage involves calibrating the beamline components, characterizing the beam, and validating the experimental conditions required to use the radiation as a research tool. 

Over the coming months, the beamline will be used in experiments conducted by invited users, who will help test and explore the capabilities of the facility. This is a crucial phase for fine-tuning operational parameters and developing experimental methodologies. 

Following this period, Tatu will be incorporated into Sirius’ regular calls for research proposals. “Very soon, we’ll begin commissioning with advanced users, and within a few months the beamline should be open to the entire scientific community,” says Raul.