“…In general, a resistive switch can attain different resistance states which are controlled by the polarity or magnitude of an applied bias resulting in pinched hysteretic I–V profiles . In recent years, resistive switching has been reported for various classes of materials ranging from sulfides (e.g., Cu 2 S, Ag 2 S) to binary oxides (e.g., TiO 2 , SiO 2 , CuO, NiO, CoO, Fe 2 O 3 , MoO, VO 2 ) over to complex oxides (e.g., SrTiO 3‐δ , (La , Sr)MnO 3 , (Pr,Ca)MnO 3 , BaTiO 3 , (La,Sr)(Co,Fe)O 3 , CeCu 3 Ti 4 O 12 ) . Among those the most extensively studied switching oxides are already processed in today's semiconductor industry as gate oxides like SrTiO 3‐δ , SiO 2 , TiO 2‐δ , Ta 2 O 5‐δ or HfO 2‐δ.…”