Patent ID: 7733684

Claim:
A data read/write device comprising: a recording layer; and means for applying a voltage to the recording layer, generating a resistance change in the recording layer, and recording data, wherein the recording layer is composed of: A x M y X 4 where A is at least one element selected from the group consisting of Na, K, Rb, Be, Mg, Ca, Sr, Ba, Al, Ga, Mn, Fe, Co, Ni, Cu, Zn, Si, P, S, Se, Ge, Ag, Au, Cd, Sn, Sb, Pt, Pd, Hg, Tl, Pb, and Bi; M is at least one element selected from the group consisting of Al, Ga, Ti, Ge, Sn, V, Cr, Mn, Fe, Co, Ni, Nb, Ta, Mo, W, Ru, and Rh; and A and M are elements that are different from each other, X is at least one element selected from the group consisting of O and N, and molar ratios x and y satisfy 0.1≦x≦2.2, and 1.8≦y≦2, respectively.