Low temperature C/T$^{3}$ peak in dipole disordered Bi$_{2}$Ti$_{2}$O$_{7}$

The presence of a low temperature peak in C/T$^{3}$ vs T, indicating excess entropy above the Debye contribution, is practically ubiquitous among both crystalline and amorphous materials. We present specific heat measurements on crystalline Bi$_{2}$Ti$_{2}$O$_{7}$, which is known to have incoherent ionic displacements leading to dipole disorder, and other related crystalline materials, including Bi$_{2}$NbInO$_{7}$, Bi$_{4}$Ti$_{3}$O$_{12}$, Y$_{2}$Ti$_{2}$O$_{7}$, and PbTiO$_{3}$, all of which exhibit excess low temperature entropy. We find that the C/T$^{3}$ peak for these samples agree roughly with a proposed scaling relation, with the peak temperature for Bi$_{2}$Ti$_{2}$O$_{7}$ being among the lowest reported for any crystalline material. We discuss our results in the context of understanding the evolution of crystalline degrees of freedom to glassy degrees of freedom through our investigations of dipole disordered Bi$_{2}$Ti$_{2}$O$_{7}$.