Chemical trend of superconducting transition temperature in hole-doped delafossite of CuAlO2, AgAlO2 and AuAlO2

We have performed the first-principles calculations about the superconducting transition temperature T c of hole-doped delafossite CuAlO2, AgAlO2 and AuAlO2. Calculated T c are about 50 K (CuAlO2), 40 K (AgAlO2) and 3 K(AuAlO2) at maximum in the optimum hole-doping concentration. The low T c of AuAlO2 is attributed to the weak electron–phonon interaction caused by the low covalency and heavy atomic mass.