Magnetic oscillator, magnetic head, and magnetic recording and reproducing apparatus

Abstract

The present invention is to be capable of suppressing magnetic white noises as far as possible. A resonant magneto-resistance effect element includes a first magnetic layer whose magnetization direction is substantially parallel to a film plane, a second magnetic film whose magnetization direction is substantially perpendicular to the film plane, and a non-magnetic layer which is provided between the first and second layers.

1 . A resonant magneto-resistance effect element comprising: a first magnetic film whose magnetization direction is substantially parallel to a film plane; a second magnetic film whose magnetization direction is substantially perpendicular to the film plane, and a first non-magnetic film which is provided between the first and second magnetic films.  
     
     
         2 . A resonant magneto-resistance effect element according to  claim 1 , comprises a stacked structure where a plurality of stacked layer are stacked via a second non-magnetic film, the stacked layer comprises the first magnetic film, the first non-magnetic film, and the second magnetic film.  
     
     
         3 . A resonant magneto-resistance effect element according to  claim 1 , wherein the first and second magnetic films are each a single film.  
     
     
         4 . A resonant magneto-resistance effect element according to  claim 1 , wherein a difference in magnitude between a shape anisotropy magnetic field of the first magnetic film and a crystalline anisotropy magnetic field in a direction perpendicular to the film plane is 500 Oe or less.  
     
     
         5 . A resonant magneto-resistance effect element according to  claim 1 , wherein a difference in magnitude between a shape anisotropy magnetic field of the second magnetic film and a crystalline anisotropy magnetic field in a direction perpendicular to the film plane is 500 Oe or less.  
     
     
         6 . A resonant magneto-resistance effect element according to  claim 1 , wherein at least one of the first magnetic film and the second magnetic film has a single magnetic domain.  
     
     
         7 . A resonant magneto-resistance effect element according to  claim 1 , wherein a thickness of each of the first and second magnetic films is 3 nm or less.  
     
     
         8 . A resonant magneto-resistance effect element according to  claim 1 , comprising a first electrode provided on opposite side of the first magnetic film from the first non-magnetic film and a second electrode provided on opposite side of the second magnetic film from the first non-magnetic film.  
     
     
         9 . A resonant magneto-resistance effect element according to  claim 8 , comprising a perpendicularly magnetizing bias film provided between the first magnetic film and the first electrode, the perpendicularly magnetizing bias film provides magnetic field substantially perpendicular to its film plane.  
     
     
         10 . A resonant magneto-resistance effect element according to  claim 1 , further comprising a parallel magnetizing bias film provided at side portions of the first magnetic film, the first non-magnetic film, and the second magnetic film, the parallel magnetizing bias film provides a magnetic field substantially parallel to film planes of the first magnetic film, the first non-magnetic film and the second magnetic film.  
     
     
         11 . A resonant magneto-resistance effect element according to  claim 1 , further comprising a perpendicularly magnetizing bias film provided at side portions of the first magnetic film, the first non-magnetic film, and the second magnetic film, the perpendicularly magnetizing bias film provides a magnetic field substantially perpendicular to its film plane.  
     
     
         12 . A resonant magneto-resistance effect element according to  claim 2 , wherein a difference in magnitude between a shape anisotropy magnetic field of the first magnetic film and a crystalline anisotropy magnetic field in a direction perpendicular to the film plane is 500 Oe or less.  
     
     
         13 . A resonant magneto-resistance effect element according to  claim 2 , wherein a difference in magnitude between a shape anisotropy magnetic field of the second magnetic film and a crystalline anisotropy magnetic field in a direction perpendicular to the film plane is 500 Oe or less.  
     
     
         14 . A resonant magneto-resistance effect element according to  claim 2 , wherein at least one of the first magnetic film and the second magnetic film has a single magnetic domain.  
     
     
         15 . A resonant magneto-resistance effect element according to  claim 2 , wherein a thickness of each of the first and second magnetic films is 3 nm or less.  
     
     
         16 . A resonant magneto-resistance effect element comprises a first and second magnetic films whose magnetization directions are substantially parallel to a film plane, and a stacked layer, the stacked layer being provided between the first and second magnetic films, the stacked layer comprising a plurality of sets of a third magnetic film whose magnetization direction is substantially perpendicular to the film plane and a non-magnetic film.  
     
     
         17 . A resonant magneto-resistance effect element according to  claim 16 , wherein at least one of the first and second magnetic films, and the third magnetic film has a single magnetic domain structure.  
     
     
         18 . A resonant magneto-resistance effect element according to  claim 16 , wherein a thickness of each of the first to third magnetic films is 3 nm or less.  
     
     
         19 . A magnetic head comprising a resonant magneto-resistance effect element according to  claim 1  as a reproducing element.  
     
     
         20 . A magnetic recording and reproducing apparatus comprising a magnetic head according to  claim 19.