Bhavesh Ramkorun, a physics graduate researcher at Auburn University, is leading a study that shows how even weak magnetic fields can strongly influence the behavior of a little-known state of matter called dusty plasma. Working with colleagues in Auburn’s Department of Physics, Ramkorun and the team found that magnetism can alter how microscopic particles form and grow inside plasmas by changing the motion of electrons.
Ramkorun, B., Thakur, S. C., Comes, R. B., & Thomas, E. (2025). Electron magnetization effects on carbonaceous dusty nanoparticles grown in <math> <mrow> <mi>Ar</mi> <mtext>−</mtext> <msub> <mi mathvariant="normal">C</mi> <mn>2</mn> </msub> <msub> <mi mathvariant="normal">H</mi> <mn>2</mn> </msub> </mrow> </math> capacitively coupled nonthermal plasma. Physical Review E, 112(4), 045211. https://doi.org/10.1103/3d3h-rkmb
Dusty plasmas consist of ionized gas that contains solid particles ranging from nanometers to micrometers in size. These particles become electrically charged and remain suspended, creating a system that behaves differently from conventional solids, liquids, or gases. Dusty plasmas are routinely produced in laboratories, but they are also common in nature, appearing in environments such as planetary rings, comet tails, and parts of the solar atmosphere. Despite their prevalence, the mechanisms that control particle growth inside these plasmas are still not fully understood.
Bhavesh Ramkorun, a physics graduate researcher at Auburn University stated,
“Plasma makes up most of the visible universe, and dust is everywhere. By studying how the smallest forces shape these systems, we’re uncovering patterns that connect the lab to the cosmos.”
In the Auburn experiments, the researchers focused on how electrons influence the formation of carbon nanoparticles. The team generated a nonthermal plasma by igniting a mixture of argon and acetylene gas, a setup commonly used to grow carbon-based nanomaterials. Under normal conditions, nanoparticles formed steadily over a period of about two minutes before leaving the plasma region. Their size and lifetime were largely governed by how electrons collided with and charged the growing particles.
When weak magnetic fields were introduced, the behavior changed noticeably. The magnetic field caused electrons to follow curved, spiral paths rather than moving freely through the plasma. This altered how electrons reached the dust particles and how charge accumulated on their surfaces. As a result, particle growth slowed, growth periods shortened, and the final nanoparticles were smaller than those formed without magnetism.
The experiments showed that electrons, despite being the lightest components in the plasma, play a dominant role in setting growth conditions once they become magnetized. By controlling electron motion, the magnetic field indirectly controlled how quickly particles accumulated material and how long they remained stable within the plasma. Small changes in magnetic conditions produced measurable differences in particle size and lifetime, highlighting the sensitivity of dusty plasmas to even modest external fields.
Co-author Saikat Thakur noted that this behavior challenges the assumption that strong magnetic fields are required to significantly affect plasma systems. In this case, relatively weak fields were enough to reorganize electron dynamics and reshape the entire growth process. This insight helps clarify why dusty plasmas observed in space can behave very differently depending on local magnetic conditions, even when other factors appear similar.
Beyond its relevance to space physics, the work has practical implications for plasma-based manufacturing. Dusty plasmas are used to produce nanoparticles for applications in electronics, coatings, and advanced materials. Being able to tune particle growth using magnetic fields could offer engineers an additional control parameter, allowing them to adjust particle size and distribution without changing gas chemistry or power levels.
The study also contributes to a broader effort to understand complex plasmas, where interactions span electrons, ions, neutral gas, and solid particles. By isolating the role of electron magnetization, the Auburn team provides a clearer link between fundamental plasma physics and real-world material outcomes. As laboratory techniques improve, such insights may help bridge the gap between controlled experiments and the diverse plasma environments found throughout the universe.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
