Description
Nanoparticles spontaneously nucleate from gaseous chemical precursors in low temperature argon plasmas, forming a chemically active nano dusty plasma that contains both the background plasma and solid particles (dust). These particles remain levitated through a balance of electric, ion drag, and gravitational forces. While suspended, they grow linearly in size until the force balance can no longer support them, at which point they leave the bulk plasma and a new growth cycle begins. This cyclic dust growth continues as long as the chemically active plasma is sustained. Recently, we observed that applying an external background magnetic field accelerates the growth cycle, that is, particles remain levitated for a shorter duration. We investigate this behavior in two types of dusty plasmas: those producing carbonaceous particles from acetylene and those producing titanium dioxide particles from titanium isopropoxide. In both systems, we find that the cycle time decreases gradually with magnetic fields as weak as 20 Gauss, eventually reaching a plateau at higher field strengths. It is possible that the magnetic field reduces the electric force acting on the nanoparticles, and weakens the overall force balance which shortens the levitation time.