Information recording/reproducing device

An information recording/reproducing device comprising:

• a stacked structure which is comprised of an electrode layer and a recording layer;
• a buffer layer which contacts with the electrode layer;
• and
• a recording circuit which records data to the recording layer by generating a phase change in the recording layer,
• wherein the recording layer is comprised of a complex compound having cations, and one of the cations is a transition element having “d” orbit where electrons are incompletely filled,
• the recording layer is comprised of CuxAyXz (0.1≦x≦1.1, 0.9≦y≦1.1, 1.8≦z≦2.2), where A includes one element selected from a group of Al, Ga, Sc, In, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ti, Ge, Sn, V, Cr, Mn, Fe, Co, Ni, Nb, Ta, Mo, W, Ru, Rh, and Pd, and X includes one element selected from a group of O, F, N, and S,
• the recording layer includes a first chemical compound having a delafossite structure, and
• the buffer layer is comprised of one of M3N4, M3N5, MN2, M4O7, MO2 and M2O5, where M includes one element selected from Si, Ge, Sn, Zr, Hf, Nb, Ta, Mo, W, Ce, and Tb.