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It is evident now that the
internal mechanism of explosive
electron emission and vacuum discharges
is determined to a considerable extent
by the dynamics of tion of the liquid
phase at the cathode surface. The
liquid phase is always present, if only
on the individual sections of solid
cathode, in every type of high voltage
vacuum discharge. What is nkre, it
presence is fixed actually even on
carbon cathodes, although the formation
of the liquid phase on it is
fundamentally inhibited, since at
normal pressures carbon sublis by
passing the iilting stage1 The
interaction between the external fields
and the liquid surface of the emitter
leads to the ergency of different
types of hydrodynamic instabilities. As
a result, the surface iuicrostructures
of different types are formed2. The
character diinsions of structures
produced have the values which provides
for the creation of the fields required
for the emission sustaining. As our
experiments show2, the development of
such instability in super-high
frequency (SHF) fields results in a
capillary wave swing, that, even with
relatively low SHF-field strengths, may
cause both field electron and field ion
emission3. In this case, the high
degree of reproducibility of small-
scale irregularities of the microrelief
of a liquid surface is, in our opinion,
the reason such emitters are highly
stable.
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