Low temperature specific heat of doped and undoped glasses

In this work we have measured the specific heat, c_p, of several glasses between 2 and 160 K. The experiments were performed in low silica calcium aluminosilicate (prepared under vacuum and room atmosphere conditions), in silicate and in fluoride glasses. The influence of neodymium, iron and cobalt in c_p values at low temperature was also investigated. The scaling proposed by Liu and Löhneysen was used to analyze the experimental data. The temperatures in which the maxima in c_p/T³, the so called boson peak, occur are discussed in terms of the Hrubý coefficient, which provides information about the glass forming ability.