Properties of exchange coupled all-garnet magneto-optic thin film multilayer structures

Abstract

The effects of exchange coupling on magnetic switching properties of all-garnet multilayer thin film structures are investigated. All-garnet structures are fabricated by sandwiching a magneto-soft material of composition type Bi 1.8 Lu 1.2 Fe 3.6 Al 1.4 O 12 or Bi 3 Fe 5 O 12 :Dy 2 O 3 in between two magneto-hard garnet material layers of composition type Bi 2 Dy 1 Fe 4 Ga 1 O 12 or Bi 2 Dy 1 Fe 4 Ga 1 O 12 :Bi 2 O 3. The fabricated RF magnetron sputtered exchange-coupled all-garnet multilayers demonstrate a very attractive combination of magnetic properties, and are of interest for emerging applications in optical sensors and isolators, ultrafast nanophotonics and magneto-plasmonics. An unconventional type of magnetic hysteresis behavior not observed previously in magnetic garnet thin films is reported and discussed.