A new magnetic recording read head technology based on the magneto-electric effect

• Published in: Journal of physics. D, Applied physics Applied physics, 2007-09, Vol.40 (17), p.5027-5033
• Main Authors: Vopsaroiu, Marian, Blackburn, John, Cain, Markys G
• Format: Article
• Language: English
• Subjects: Applied sciences; Electronics; Exact sciences and technology; Magnetic devices; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0022-3727; 1361-6463
• DOI: 10.1088/0022-3727/40/17/003

The existing magnetic recording read head technologies use one of the well-known magneto-resistance effects (i.e. anisotropic magneto-resistance, giant magneto-resistance or tunnelling magneto-resistance (TMR)) to read back the data from the magnetic recording medium. These are usually sophisticated devices that require a dc test current flowing through the sensor stack in order to measure its change in resistance (i.e. amplitude response signal) as a function of the fringing magnetic flux of the recorded bits, when the reader moves along the recorded track. In this paper, we propose the design of a new kind of highly sensitive read sensor for magnetic recording heads, which directly produces a voltage response without the need for a test current. This new design is based on the magneto-electric effect in laminated multiferroic materials. Such a magnetic read head is much simplified in terms of sensor construction (i.e. number of layers involved and horizontal biasing requirements) and has a range of potential advantages including similar sensitivity to that of the TMR heads, reduced power consumption, better thermal performances, excellent high frequency operation and reduced cost of production.