An ultrafast laser enables the manipulation of 2D materials in new generation devices

Some 2D materials such as graphene, silicene (other than silicone), black phosphorus, and transition metal dichalcogenides (TMDs) are electrically and mechanically superior to others.

These materials could help build fast photodetectors, advanced sensors, high-tech flexible electronics and solar cells much more efficient than those we use today.

However, scientists currently do not have a perfect technique for manipulating and processing these 2D materials, which prevents us from realizing their potential. However, the results of a new study reveal a solution to this problem.

A team of researchers from Finland’s University of Jyväskylä and Serbia’s University of Novi Sad suggested that ultrafast laser processing could help realize the potential of two-dimensional materials.

The advantage of ultra-fast laser processing

Currently, 2D materials such as graphene and TMDs are manipulated using continuous wave (CW) and long pulse optical methods. These methods involve shooting beams of light at the surfaces of 2D materials to induce changes in their physical and chemical properties.

However, both continuous wave and long-pulse methods have one major limitation. When light strikes a material continuously in the form of waves or bursts of energy, it produces heat which, if not managed properly, can damage the material.

This is where ultrafast laser processing can make a huge difference. This technique uses ultrashort laser pulses to modify materials with high precision and minimal thermal damage.

It can make changes in materials at the nanoscale. “By using the synergy effect between energy states in atomic layers and ultrafast laser irradiation, it is possible to achieve unprecedented resolution of several nanometers,” the authors of the study note.

“The ability to manipulate 2D materials on such a large scale opens up numerous opportunities to develop novel photonics, electronics and sensor applications,” they added.

The technology hasn’t left the lab yet

Working at the atomic scale, ultrafast laser processing can efficiently enable processes such as exfoliation (peeling off), reduction (adding electrons to improve electrical conductivity), and doping (adding impurities to modify material properties) in 2D materials.

These processes are key to changing the physical and chemical properties of 2D materials, enabling their use in the development of next-generation electronic and photonic devices.

However, ultrafast laser processing is a technique that is still in the development phase. Even in a laboratory setting, it involves the use of expensive equipment and poses several challenges related to optimization and scaling. “The technology is currently evolving from a laboratory concept to a practical production tool,” the study authors said.

Hopefully, further research will shed light on ways to make this approach more practical and discover its other unknown benefits.

The study was published in the journal Advanced materials.