Superconductor magnetic reading and writing heads

Abstract

Read/write heads for exchanging information with a magnetic media in either vertical or horizontal recording modes include SQUID detectors coupled to the magnetic flux path of the head. Selective use of superconducting material improves the data interchange operating efficiency of the read/write head and its coils. Magnetic paths associated with head elements are confined and directed by superconducting material to produce compact data with minimal power requirements. Magnetic read/write heads containing Josephson junction or SQUID detectors and which are encased in superconductive material allow high density data recording and highly sensitive data detecting. Data density is also improved by selected application of superconductive material to magnetic read/write heads constructed for perpendicular recording.

What is claimed is: 
     
       1. A head for interfacing with a magnetic recording media comprising: a member of magnetic material forming at least a portion of a magnetic flux circuit ending with a pole face surface in interfacing relation to the media for establishing a main pole in proximity to the media in said magnetic flux circuit,   magnetically responsive means in magnetically coupled relation to said magnetic flux circuit,   means encasing at least a portion of the external surfaces of said member with superconductive material except for the media interfacing portion of said pole face surface, said encasing means including superconducting material substantially surrounding said magnetic flux circuit in proximity to said pole face surface, and   means establishing an environment for said superconductive material at a temperature for maintaining said superconductive material in its superconductive state,   whereby magnetic flux in said magnetic flux circuit associated with said encasing means is concentrated within said magnetic flux circuit while placement of said pole face surface in proximity to the recording media permits sensitive magnetic flux controlled information exchanges between the media and said head.   
     
     
       2. A head in accordance with claim 1 wherein said terminal portion of said magnetic flux circuit forming member concludes with a smaller cross-sectional area at said pole face surface relative to the cross-sectional area of said magnetic circuit at the end of said terminal portion opposite said pole face surface, an said encasing means includes means constructed of superconductive material and arranged to encase said magnetic circuit throughout the length of said magnetic flux circuit terminal portion and ending in proximity to said main pole for concentrating magnetic flux therefrom into intercepting relation with a magnetic storage layer of the media, whereby introduction of magnetic flux to said magnetic flux circuit produces perpendicular data recording in the media. 
     
     
       3. A head in accordance with claim 2 which includes auxiliary flux returning means magnetically communicating with said member for substantially completing said magnetic flux circuit and ending with a pole face surface in interfacing relation to the media for completing said magnetic circuit as an auxiliary pole. 
     
     
       4. A head in accordance with claim 3 wherein said member pole face surface is of a relatively small area compared to said flux returning means auxiliary pole face surface area for establishing perpendicular data recording in the media under said member surface while not magnetizing the media under said auxiliary flux returning surface. 
     
     
       5. A head in accordance with claim 1 in which said magnetically responsive means further includes SQUID means coupled to said magnetic flux circuit for detecting magnetic flux therein. 
     
     
       6. A head in accordance with claim 5 in which said magnetically responsive means further includes a coil magnetically coupled to said magnetic flux circuit, and means selectively energizing said coil for introducing magnetic flux changes to said magnetic flux circuit.   
     
     
       7. A head in accordance with claim 1 in which said magnetically responsive means includes a coil magnetically coupled to said magnetic flux circuit, and means selectively energizing said coil for introducing magnetic flux changes to said magnetic flux circuit.   
     
     
       8. A head in accordance with claim 7 wherein a layer of said superconducting encasing means forms a barrier between said coil and said magnetic circuit, said layer being constructed and arranged for shifting from a superconductor state to a normal magnetic flux transmitting state in response to operation of said selectively energizing means and for remaining in said superconductor sate whenever said coil is not energized. 
     
     
       9. A head in accordance with claim 7 wherein said coil is composed of at least one loop of superconductive material. 
     
     
       10. A head in accordance with claim 9 wherein said magnetically responsive means further includes a magnetic transducer coupled to said magnetic circuit for producing an output correlated to data contained on the media. 
     
     
       11. A head in accordance with claim 10 wherein said transducer is a SQUID coupled to intercept magnetic flux present in said magnetic circuit. 
     
     
       12. A probe type head for interfacing with at least one data track on a magnetic media comprising: an elongated, thin film of magnetic material having one end face with a width corresponding to the track width on the magnetic media and forming the main pole of the head,   a coating of superconductor material encasing at least a portion of the length of said thin film except said one end face,   means establishing an environment for said superconductor material at a temperature for maintaining said material in a superconductive status,   magnetically responsive means in magnetically coupled relation to said thin film, and   means assembling said thin film, said coating and said magnetically responsive means for cooperating with structure associated with the media so as to position said thin film in generally perpendicular relation .Iadd..[.tot he.]. .Iaddend..Iadd.to the .Iaddend.magnetic media with said main pole end face in proximity to the data containing tracks on the media for magnetic communication between said magnetically responsive means and the media.   
     
     
       13. A head in accordance with claim 12 which includes magnetic material in overlying relation to said thin film from the end opposite said track width end to a point in spaced relation from said track width end. 
     
     
       14. A head in accordance with claim 13 wherein said superconductor material coating encases said thin film from said track width end face to said spaced relation point along the length of said thin film. 
     
     
       15. A head in accordance with claim 14 wherein said magnetically responsive means includes a coil magnetically coupled to said overlying magnetic material, and means for selectively energizing said coil for introducing a magnetic flux pattern into said thin film corresponding to data for recording on the media. 
     
     
       16. A head in accordance with claim 14 wherein said magnetically responsive means includes a transducer connected in the magnetic circuit of said thin film and said overlying magnetic material for detecting magnetic flux corresponding to data contained magnetically on the media. 
     
     
       17. A head in accordance with claim 16 wherein said transducer includes a SQUID for sensing magnetic flux present in said thin film, and said coil is composed of at least one loop of superconductive material.   
     
     
       18. A head in accordance with claim 14 which further includes an auxiliary pole means of magnetic flux conducting means connected for completing a magnetic circuit into an interface in proximity to the media in spaced relation to said main pole face with said magnetic circuit including said thin film, said overlying magnetic material and said auxiliary pole means. 
     
     
       19. A head in accordance with claim 18 wherein said main pole track width end is of an area for causing magnetization of the media when flux of a preselected density is introduced to said magnetic circuit while magnetic flux of said predetermined density passing through the area of said auxiliary pole means interface does not change the magnetic state of the media. 
     
     
       20. A head in accordance with claim 19 wherein said coating substantially encases the external surfaces of said head with superconductor material except for the media interface of said main pole face and the media interface of said auxilliary magnetic flux conducting means. 
     
     
       21. A head in accordance with claim 20 wherein said magnetically responsive means includes a SQUID in said magnetic flux circuit. .Iadd. 
     
     
       22.  An information storage device, comprising: a medium support mounted so as to be rotatable about an axis of rotation; a magnetic recording medium deposited upon a surface of said medium support;   a read/write head positioned adjacent the surface of said medium support upon which said magnetic recording medium is deposited;   means for writing a magnetic pattern into said recording medium, said means for writing being mounted on said read/write head; and   means for reading the magnetic pattern in said recording medium, said means for reading being mounted on said read/write head and including a superconducting quantum interference device..Iaddend. .Iadd.23. The information storage device of claim 22 wherein said medium support is a disk..Iaddend. .Iadd.24. The information storage device of claim 22 further including   means for cooling said superconducting quantum interference device to a temperature at which the material of said device is in a superconducting   
     
     
        state..Iaddend. .Iadd.25.  The information storage device of claim 22 further including a vacuum tight housing that encloses said medium support, said read/write head, said means for writing, and said means for reading..Iaddend. .Iadd.26. The information storage device of claim 22 wherein said superconducting quantum interference device comprises a single loop of conductor material..Iaddend.