Ternary (60-x)V2O5–xSb–40TeO2 oxide glasses
(with 0 B x B15 in mol%), prepared using the usual
melt quenching method, were investigated electrically (at
the presence of high-dc electric fields) within the temperature
range of 298–375.3 K at different electrode distances.
The current–voltage characteristics show increasing deviations
from Ohm’s law at electric fields of about[103 V/
cm. This behavior can be attributed to the Pool–Frenkel
effect, which usually occurs at the mentioned electric
fields. At higher fields, switching (from low conduction
state to higher conduction state) or negative resistance
phenomena were observed at a threshold voltage (Vth). The
threshold voltage for beginning the switching/negative
resistance shows a decreasing trend with increasing in
temperature and also with decreasing of electrode distance.
An electrothermal model (based on the Joule heating effect
in the current filament) is proposed to interpret the
observed electrical properties. Also, the lowering factor of
potential barrier (bPF) in Pool–Frenkel effect, heat dissipation
factor, and electrical activation energy of the present
samples were determined. In each sample, the increase of
bPF with temperature can explain the phonon-assisted
hopping conduction.