Forming self-pulsing plasma into a 3D continuous pattern

Even as research gains ground in studying and replicating the formation of natural patterns – from the intricate array of shapes on leaves to leopard spots – results are largely confined to 1D or 2D designs. Remarkably,Yu et al.reports the creation of the first continuous 3D pattern made from self-pulsing plasma within a dielectric barrier discharge system (DBDS).

ADBDS produces self-pulsing plasma, in this case composed of electrically charged air and argon gas, which is used for material surface treatment and other applications. Natural patterns produced by plasma also occur in DBDS.

To manipulate filaments of plasma into a continuous3D design, the researchers integrated a new technique within a conventional DBDS to introduce surface discharges.A copper ring was placed in a water electrode, and a three-layer glass frame was used to produce three gas gaps. The complex interactions between the surface discharges and the volume discharges caused the volume discharges to bend through the gaps to form the 3D pattern.

The findings build off research in 2016 led by Lifang Dong, an author and co-inventor of the new DBDS technique. In the previous work, a discrete 3D pattern was produced. For the continuous pattern, the researchers increased the discharge gap sizes to create the surface discharge.

The new technique not only explores pattern formation but also improves plasma processing efficiency, because now three gaps can be used instead of one.

“Three surfaces of the sample inserted between electrodes can be processed simultaneously,” Dong said. “It is also adjustable, enabling the processing of both thick and thin samples.”

Source: “Formation mechanism and application of a three-dimensional pattern in dielectric barrier discharge system,” by Guanglin Yu, Lifang Dong, Liting Guo, Fucheng Liu, Caixia Li, Yaya Dou, Chenhua Ren, and Yuyang Pan, Physics of Plasmas (2020). The article can be accessed at https://doi.org/10.1063/1.5138231 .