Microwave resonant cavity modes

The cylindrical resonant cavity which operates in the TE0n mode is another very useful design. The Hi and Ei field lines of force for this cavity are shown in Fig. 9. One commercially available cavity of this type has a bottom which can be screwed in and out, thus changing the resonant microwave frequency over a limited range. 

By far a very efficient applicator, particularly for the syntheses on a small scale (< 50 ml), is a single-mode resonant cavity, in which only one mode of microwave propagation is permitted and hence the field pattern is well defined so the material can be positioned accordingly (Fig. 3.6). 

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