The problem with using either the SiC tube or a carbon rod is the loss of the magnetic field.
SPP formation is opto-magnetic. Resistance wire coils have enough amp-turns to provide a small axial magnetic field, and this appears to be important. See the papers on the Letts/Cravens effect – a small field appears to be preferable to a larger one This magnetic field would be lost with a one-turn rod or tube. From: Hoyt A. Stearns Jr. Silicon carbide is a good enough electrical conductor it can be made to be the vessel and heater at the same time ( I've tried using it as a heater -- works fine). From: Bob Higgins Daniel, I got an email response to you from Dennis Cravens (who reads Vortex-l): "One easy way is a carbon welding rod. ---Cheap and most have copper coatings that can be easily pealed off and also be used for easy connections. They are also useful for current shunts." Daniel Rocha wrote: Bob, it seems that Parkhomov is low on budget. Isn't there a cheaper way to heat that? Like, removing the graphite from a pencil and using it to heat?