Glasses containing significant amounts of atoms carrying large nuclear electric quadrupole moments show very surprising effects both in the low frequency and the GHz regime.
The nucleus of Ho-165 carries a very large electric quadrupole moment and therefore appears to be a good candidate to investigate the influence of these quadrupole moments down to very low temperatures.The optical filter glass HY-1 containing several percent of holmium.
We measured by using an LC-resonator technique the dielectric permitting of this multicomponent glass at 30 MHz for temperatures between 7 mK and several Kelvin.
The real part of the permittivity – measured the relative change of the capacity – shows a slope ratio of -1 : 3. The dielectric loss is surprisingly high.
