FIELD-HEATED, FIELD-COOLED, AND ZERO-FIELD-HEATED STATIC PERMITTIVITYOF THE DEUTERON GLASS RB1-X(ND4)XD2ASO4

Dielectric permittivity and remanent polarization measurements have be en performed in deuterated rubidium ammonium dihydrogen arsenate with x = 0.28. Upon cooling the crystal, there is only the ''transition'' t o the deuteron glass state. Static permittivity measurements were carr ied out along the a tetragonal axis at two different heating and cooli ng rates. Applying an external dc electric field along the a axis crea tes a bias which forces the acid deuteron in the O-D ... O bond to lie at one end as opposed to the other as the temperature is lowered. Thi s gives rise to a static permittivity (almost-equal-to polarization an d/or field) which freezes in below the glass ''transition'' temperatur e T(g). On switching the external electric field off, a remanent polar ization is observed which vanishes above T(g) as the ''frozen'' deuter ons acquire more and more energy to overcome the random potential barr iers. A theoretical fit with one adjustable parameter is seen to be in good agreement with the experimental results.