Physics and Design of Hard Disk Drive Magnetic Recording Read Heads

  • Stefan MaatEmail author
  • Arley C. Marley


Magnetic recording heads always have been on the forefront of technology. A finished magnetic recording head that is manufactured in high volume is the outcome of a coordinated effort of various scientific and engineering disciplines. This chapter will focus on the physics and design of modern magnetic recording read heads. It will explain the underlying concepts of thin film magnetism and electron transport in nanostructures and describe the aspects of device scaling, magnetic stabilization, signal-to-noise considerations, and read-back performance of currently employed tunnel magnetoresistive read heads. An outlook on possible future read-head technologies such as current-perpendicular-to-the-plane giant magnetoresistance, scissor, two-dimensional magnetic recording, and spin-torque sensors will be given.


Tunnel Junction Areal Density Tunnel Barrier Heusler Alloy Free Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of Abbreviations


Magnetic damping constant


Bulk spin-scattering parameter


Interface spin-scattering parameter


Angle of layer magnetization with respect to the magnetic field


Media transition length


Air-bearing surface


Antiferromagnetic coupling layer




Anisotropic magnetoresistance


Body-centered cubic


Bias point




Current in plane


Cap layer


Chemical mechanical polishing


Current perpendicular to the plane


Free layer


Gyromagnetic ratio


Gigabit/square inch


Giant magnetoresistance


Magnetic field


Magnetic out-of-plane stiffness field


Hexagonal close packed


Demagnetization field


Hard-bias field


Magnetic in-plane stiffness field


Head-media spacing


Ion beam deposition


International Business Machines


Boltzmann constant


Spin-diffusion length


Free layer magnetization




Remanent magnetization


Magnetic read width


Saturation magnetization


Offtrack capability


Offtrack position


Spin polarization


Pinned layer


Physical vapor deposition


Pulse width




Sensor resistance at zero field


Resistance-area product


Alternating current resistance


Sensor resistance in the antiparallel state


Direct current resistance


Read gap


Sensor resistance for negative media field


Sensor resistance for positive media field




Reference layer


Sensor resistance in the parallel state


Noise spectral density


Bottom shield


Top shield


Stripe height


Seed layer


Signal-to-noise ratio


Squeeze track pitch


Shield-to-shield spacing


Absolute temperature in Kelvin




Tunnel barrier


Two-dimensional magnetic recording


Thermal flight-height control


Tunnel magnetoresistance


Track width




Bias voltage


Free layer volume


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Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  1. 1.Magnetic Recording Heads DevelopmentHGST, a Western Digital CompanySan JoseUSA
  2. 2.HGST, a Western Digital CompanySan JoseUSA

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