A single dominating mode microwave reactor

A single dominating mode microwave reactor, wherein said single dominating mode microwave reactor propagates microwaves in a TE10 fundamental mode, said single dominating mode microwave reactor comprising:

• a reactor chamber;
• at least one antenna for feeding single mode microwaves into said reactor chamber connected to said reactor chamber, wherein said at least one antenna for feeding single mode microwaves comprises:
• a transmitter configured to transmit microwaves, wherein the transmitter comprises a microwave inlet and a microwave outlet;
• a filter, which comprises a mode filter and, wherein said mode filter comprises metal rods or cylinders separated from each other and located at the microwave outlet of the transmitter, wherein said metal rods or cylinders are separated from each other by less than a quarter wavelength of transmitted microwaves in the direction of propagation of the microwaves and by less than a half wavelength of transmitted microwaves in a direction orthogonal to the direction of propagation of the microwaves.