The impact of plasma pattern formation on particle growth in strongly magnetized, low temperature plasmas*

Over the last three decades, plasma scientists have learned how to control a new type of plasma system known as a “complex” or “dusty” plasma.  These are four-component plasma systems that consist of electrons, ions, neutral atoms, and charged, solid, nanometer- to micrometer-sized particles.  The vast majority of dusty/complex plasma experiments have involved the suspension of charged, micron-sized particles in plasmas.  The particles are suspended due to an exquisite balance between gravitational, electrostatic, and drag forces.  With the addition of a magnetic field, the properties of the background plasma and the dust are modified as the dynamics of the electrons, then the ions, and finally the charged dust grains become dominated by the magnetic field.  

Since the mid-2000s, several experimental devices have been built around the world to explore the physics of dusty plasmas in strongly magnetized plasmas.  One of these devices, the Magnetized Dusty Plasma Experiment (MDPX) device at Auburn University is a flexible, high magnetic field (up to 4 T) research instrument with a mission to serve as an open access, shared user facility for the dusty plasma and basic plasma research communities.  When the magnetic field is sufficiently large, B ≥ 1 T, a variety of emergent phenomena are observed including the formation of self-ordered plasma structure, specifically plasma filamentation along the magnetic field direction, as well as new types of imposed spatial ordering of the dust particles.  This presentation will discuss recent studies of nanoparticle formation in strongly magnetized, reactive argon-acetylene capacitively coupled plasmas.  Experiments and simulations will discuss how filamentary structures are formed in the plasma.  Additional experiments will show how the presence of these filaments influence the morphology of the grown nanoparticles.