The evil geniuses at NASA Ames Research Center are trying to create super intelligent soccer balls with a top-secret vaporized serum! … er … wait, no. They’re just studying the aerodynamics of the official World Cup ball - the “Brazuca.”
This coaxial microwaveplasma source (MPS) generates plasma without using a magnetic field. It works like an inverse luminescent tube excited by microwaves. The coaxial microwave plasma generator consists of a copper rod (antenna) as inner conductor surrounded by quartz tube filled with argon gas, the plasma is the outer conductor. The inside of the tube is at atmospheric pressure whereas the outside is at low pressure. The plasma formed around the quartz tube acts as an outer conductor in such a way that a spatially extended surface wave is created, just in an equivalent (‘inverse’) situation to that found in the Surfatron source (where the plasma is inside the tube instead of outside).
The microwave with a frequency of 2.45 GHz generated by two magnetrons is fed into the copper rods at both ends. On the outside of the tube, in the low pressure, the microwave fields ignite the plasma. The plasma represents a conductive medium so by increasing microwave power the plasma grows from both ends along the tube, and a homogeneous plasma is formed. The high power microwave breakdown at atmospheric pressure leads to the formation of filamentary structures. These striations or string-like structures, also known as birkeland currents, are seen in many plasmas, like the plasma ball, the aurora,lightning,electric arcs, solar flares, and even supernova remnants.
Colloidal quantum dots incorporated in ionic salts (bottom, NaCl matrix) are more brightly photoluminescent than they are in solution (top, aqueous). Changing quantum dot size and/or composition yields different emission colors, allowing device makers to tune the optical properties of the material.