Table 1 Sample description

 Substrate and layers

S1

Si(001)\SiO₂\150 nm Al\10 nm CuPc\60 nm α-NPD\70 nm Alq₃\20 nm Al

S2

Si(001)\8 nm MgO\15 nm Fe\1.8 nm MgO\10 nm CuPc\60 nm α-NPD\70 nm Alq₃\20 nm Al

S3

Si(001)\8 nm MgO\15 nm Fe\10 nm CuPc\60 nm α-NPD\70 nm Alq₃\20 nm Al

S4

Si(001)\SiO₂\15 nm poly-Fe\10 nm CuPc\60 nm α-NPD\70 nm Alq₃\20 nm Al

S5

Si(001)\8 nm MgO\15 nm Fe\1.8 nm MgO\15 nm CuPc\60 nm α-NPD\70 nm Alq₃\20 nm Al

S6

Si(001)\8 nm MgO\15 nm Fe\1.8 nm MgO\5 nm CuPc\60 nm α-NPD\70 nm Alq₃\20 nm Al

S7

Si(001)\8 nm MgO\15 nm Fe\1.8 nm MgO\1 nm CuPc23\60 nm α-NPD\70 nm Alq₃\20 nm Al