Correlation Functions and Corner Transfer Matrix of the Chiral Potts Model

We use the Density Matrix Renormalization Group technique to compute correlation functions of the Z_3-chiral Potts quantum chain in the massive regimes. Chains of up to 70 sites are used and a clear oscillatory behavior is found. We also check the relation between the density matrix spectrum and the Corner Transfer Matrix spectrum pointed out by Nishino and Okunishi, using Baxter's low-temperature formulae for the chiral Potts Corner Transfer Matrix eigenvalues. We find very good agreement.