Research

Complex Plasma

Most of my research centers around complex plasma also known as dusty plasma. A dusty plasma is simply a normal plasma consisting of electrons, ions, and excited neutrals but with the addition of micro sized particles that become charged as well. These particles provide a rich environment for additional dynamics and wide ranging phenomena. These plasmas are common throughout the universe; appearing in comet tails, planetary rings, and the interstellar clouds. They are also very important for plasma industrial processing. I have researched a number of phenomena via dusty plasmas such as waves and instabilities mostly from an experimental standpoint but also theoretically as well. I have extensive experience designing experiments in complex plasma. Some experimental setups I have used in the past are shown in the images below.

Dusty plasma permits easily identifiable phenomena via the illuminated dust particles. Shown below is a photo of clearly visible plasma waves a chamber developed for nanoparticle growth.

Precursor Solitons

Precursor solitons are a nonlinear fluid phenomenon that travel ahead of a moving object. These waves are similar to the wakes created behind a moving object except in the opposite direction. This phenomenon was known for situations such as moving ships in water but not plasma systems. My earlier research was the first to produce these waves. This phenomena is ow an extensively studied topic. It is also potentially useful for helping solve the problem of space debris as Physics Buzz pointed out when the work was first published. I am working on this particular issue in 2022 as part of a Department of Defense grant to establish feasibility of the technology.

Microgravity

Complex/dusty plasma is strongly dictated by the gravitational force and the particles levitate in a thin layer. When gravity is largely removed, as in outer space, the particles fill a larger volume of the plasma which enables a more vast array of studies. The Plasmakristall-4 (PK-4) on board the International Space Station is ideally suited for studying the dynamics of complex plasma. For example, some of my previous research on PK-4 involved studying the self excitation of density waves in a complex plasma. Under polarity reversal, the wave pattern exhibited bifurcations as shown in the picture below.

Atmospheric Pressure Plasma

Atmospheric pressure plasma is a relatively new area of plasma research that is quickly growing, largely unexplored, and highly promising for societal benefit. These plasmas have proven useful for a number of technological applications including: plasma medicine, syngas production, nitrogen fixation for agriculture, water purification, and much more. Certain reactive species such as oxygen are extremely useful for the applications mentioned previously. My research in this area focused on metastable oxygen and the emission of the "auroral" green line resulting from the emission between oxygen metastable states at 557.7 nm. Shown below is a photo of a plasma jet treating a sample of water.