hydrostatic pressure effect on the gunn threshold electric effect in n-insb
abstract
the gunn effect as a function of pressure has been
studied in n~type insb. the gunn threshold field is found to
decrease with increasing pressure reaching a minimum at p ~ 9
kbars. it then increases while the oscillations weaken with increasing
pressure up to 12 kbars. low field hall and conductivity
measurements have also been made in an attempt to obtain a possible
explanation for the threshold minimum. it is observed that the
impurity level moves away from the conduction band approximately
exponentially with increasing pressure. by 9 kbars the donor ionization
energy is large enough that considerable freeze-out or deionization
of donor states occurs. the reduction in carrier number
is unfavourable to the gunn process and hence leads to an increase
in the threshold field for pressures above 9 kbars.
collections
- retrospective theses [1604]