  The CUPID-0 experiment searches for neutrinoless double beta decay
($0\nu\beta\beta$) using the first array of enriched Zn$^{82}$Se scintillating
bolometers with double (heat and light) read-out. To further enhance the
CUPID-0 detector performances, the heat-light correlation has been exploited to
improve the energy resolution. Different decorrelation algorithms have been
studied and the best result is the average reduction of the full width at half
maximum (FWHM) energy resolution to $(90.5\pm0.6)~\%$ of its original value ,
corresponding to a change from $\text{FWHM}=(20.7\pm0.5)~\text{keV}$ to
$\text{FWHM}=(18.7\pm0.5)~\text{keV}$ at the 2615 keV $\gamma$ line.
