> An air gap does have resistance, so there will be resistive heating just like in normal chips.
They also mentioned putting these in a vacuum. Presumably that won't have as much resistance as an air gap.
They also mentioned putting these in a vacuum. Presumably that won't have as much resistance as an air gap.
If that were true, vacuum tubes (used for radio and early computers) wouldn't work.
The key to the function is the heating of the cathode filament. Vacuum tube designs that use a separate heating current (which is, today, most of them) do not conduct if the heating current is not applied. "Cold cathode" type tubes are not vacuum tubes-- they are typically filled with a low-pressure gas.
Vacuum: isolator.
Vacuum filled with electrons: not so good isolator.
Diamond is almost perfect though, at 20 gigavolts per metre, and that only given if the diamond has at least some microscopic imperfections.
Given a small enough distance, arcing is possible between 2 surfaces in vacuum as charges are ejected from the surface (that’s how vacuum tubes and these transistors work).
Just because EM waves can propagate in vacuum does not mean you can induce a current density.
Obviously you can't induce a current in vacuum, but you can definitely convert EM waves to current flux in a receiving structure.
> Obviously you can't induce a current in vacuum ...
Yes. I wrote that second part because 'mmmBacon seemed to be arguing that one could induce a current in vacuum; that because vacuum has a characteristic impedance, it isn't an insulator (i.e. can support current because it has characteristic impedance).