Michael Mallary

Last updated
Michael L. Mallary
Michael Mallary 1990.jpg
Michael Mallary, Lake Arrowhead, 1990
Born (1945-05-06) May 6, 1945 (age 78)
New Rochelle, New York
Alma mater MIT, Caltech
Occupation(s)Engineer, Inventor, Author
Employer(s) DEC, Seagate, Western Digital
Awards
  • IEEE Fellow, 2007
  • IEEE Magnetics Society Distinguished Lecturer, 2009
  • IEEE Magnetics Society Achievement Award, 2013

Michael L. Mallary is an engineer, physicist, inventor, and author who is noted for his contributions in the areas of magnetic recording and data storage on hard disk drives (HDD). [1] [2] His work has concentrated on developing and optimizing magnetic components to maximize data storage density. In particular, he is responsible to inventing the 'trailing-shield' write head used universally in modern HDDs. Mallary is a Fellow of the Institute of Electrical and Electronics Engineers and recipient of the IEEE Magnetics Society Achievement Award.

Contents

Background and education

Michael (Mike) Mallary, born May 6, 1945, was raised in Berkeley, California. His mother was an advertising executive and his father was the sculptor Robert Mallary. He attended schools in Los Angeles, California and New York City. He attended Archbishop Stepinac High School where he built a Jacob's Ladder and a crude electron microscope as science projects. [2]

Mallary received the S.B. degree in physics from the Massachusetts Institute of Technology, Cambridge, in 1966 working under John King. He received his Ph.D. degree from the California Institute of Technology in 1971 [2] writing a thesis on high-energy physics [3] under the direction of Prof Frank J. Sciulli.

From 1972 to 1974, Mallary was a post doctoral fellow at Rutherford Laboratory. [1]

Career

In 1974, Mallary joined the Magnetic Corporation of America in Waltham, Massachusetts, designing large superconducting magnets intended for nuclear fusion, high energy physics, magnetic separation, power generation, etc. [2]

Trailing Shield Concept invented by Mallary. This head design provides higher field gradients and more advantageous field angles for high-density Perpendicular Magnetic Recording. It is ubiquitous in Hard Disk Drives (HDD). Trailing Shield Write Head.jpg
Trailing Shield Concept invented by Mallary. This head design provides higher field gradients and more advantageous field angles for high-density Perpendicular Magnetic Recording. It is ubiquitous in Hard Disk Drives (HDD).

In 1980, Mallary joined Digital Equipment Corporation (DEC) in Shrewsbury, Massachusetts, as a head modeler and designer to support their effort to produce thin film heads for the RA90 disk drive. Bob Rottmayer [5] was the head of the group. At DEC Mallary came up with the idea of the so-called "Diamond Head". [6] This novel approach basically wrapped the yoke around the coil twice - effectively doubling the number of turns. (Maximizing readback voltage is always of paramount importance. This inductive head design was widely deployed, but it was eventually upstaged by the advent of magnetoresistive heads).

From the early 1990s to 2008, Mallary worked for a succession of HDD companies including Rocky Mountain Magnetics, MKE, Quantum, Maxtor, and Seagate working mainly on head design but also on manufacturing aspects such as servowriting. [1] It was during this period that he became involved with the International Storage Industry Consortium (INSIC) on the Extra High Density Recording (EHDR) project [7] working with Mason Williams, Mark Kryder, Dave Thompson and others. The need for continued increases in areal data density led to an intense focus on perpendicular recording which offered the potential of areal-densities up to 1 Terabit per square inch. [8] [9] Earlier at DEC in 1985, Mallary had invented the trailing shield (or shielded-pole) write head [10] for perpendicular recording. This design is able to reach higher recording areal-densities because it provides higher field gradients and more advantageous field angles than a conventional monopole head (see diagram). Perpendicular recording technology is presently used in all hard disk drives and Mallary's trailing-shield head design is ubiquitous.

In 2009, Mallary joined Western Digital in San Jose working on advanced recording technologies including Heat-Assisted Magnetic Recording (HAMR) and Microwave Assisted Magnetic Recording (MAMR).

Awards and recognition

In 2007, Mallary was elevated to IEEE Fellow for "contributions to recording devices". [11]

In 2009, Mallary was selected as a Magnetics Society Distinguished Lecturer and gave presentations worldwide with the title "The Evolution and Revolutions in Disk Drive Recording". [12]

In 2013, Mallary received the IEEE Magnetics Society Achievement Award for "sustained contributions to thin film magnetic recording write head designs; most notably for the invention of the shielded write head structure for perpendicular recording". [1]

In June 2019, Mallary was interviewed by Grant Saviers and Tom Yamashita as part of the Computer History Museum Oral History Series. [2]

Patents and publications

Mallary is an author or coauthor on around 100 U.S. patents. [13] These cover a variety of areas although bulk of them are associated with magnetic write head design for HDDs and, in particular, the invention of the trailing-shield write head for perpendicular recording. [10] Mallary is also the author or coauthor of about 50 technical publications again focussed on magnetic recording for hard disk drives and often in collaboration with academia. [14] [15]

Mallary wrote the chapter that details the operation and design of magnetic recording heads in The Physics of Ultra High Density Magnetic Recording, a book edited by M. Plumer, J. van Ek, and D. Weller published in 2001. [16]

Mallary is the author of a book [17] and a video [18] on cosmology and evolution entitled “Our Improbable Universe: A Physicist Considers How We Got Here” first published in 2004 with a second edition in 2018. [19] The book details how highly tuned (and hence improbable?) are the various constants that determine our physical universe. The book then goes on to examine evolution and society from a similar perspective. [20]

Mallary is an advocate and activist for the use of nuclear power to mitigate the effects of climate change [21] [22]

Related Research Articles

<span class="mw-page-title-main">Hard disk drive</span> Electro-mechanical data storage device

A hard disk drive (HDD), hard disk, hard drive, or fixed disk, is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored and retrieved in any order. HDDs are a type of non-volatile storage, retaining stored data when powered off. Modern HDDs are typically in the form of a small rectangular box.

<span class="mw-page-title-main">Hard disk drive platter</span> Circular disk on which magnetic data is stored in a hard disk drive

A hard disk drive platter or hard disk is the circular magnetic disk on which digital data is stored in a hard disk drive. The rigid nature of the platters is what gives them their name. Hard drives typically have several platters which are mounted on the same spindle. A platter can store information on both sides, typically requiring two recording heads per platter, one per surface.

In computer data storage, partial-response maximum-likelihood (PRML) is a method for recovering the digital data from the weak analog read-back signal picked up by the head of a magnetic disk drive or tape drive. PRML was introduced to recover data more reliably or at a greater areal-density than earlier simpler schemes such as peak-detection. These advances are important because most of the digital data in the world is stored using magnetic storage on hard disk or tape drives.

<span class="mw-page-title-main">Magnetic storage</span> Recording of data on a magnetizable medium

Magnetic storage or magnetic recording is the storage of data on a magnetized medium. Magnetic storage uses different patterns of magnetisation in a magnetizable material to store data and is a form of non-volatile memory. The information is accessed using one or more read/write heads.

Density is a measure of the quantity of information bits that can be stored on a given length of track, area of the surface, or in a given volume of a computer storage medium. Generally, higher density is more desirable, for it allows more data to be stored in the same physical space. Density therefore has a direct relationship to storage capacity of a given medium. Density also generally affects the performance within a particular medium, as well as price.

Perpendicular recording, also known as conventional magnetic recording (CMR), is a technology for data recording on magnetic media, particularly hard disks. It was first proven advantageous in 1976 by Shun-ichi Iwasaki, then professor of the Tohoku University in Japan, and first commercially implemented in 2005. The first industry-standard demonstration showing unprecedented advantage of PMR over longitudinal magnetic recording (LMR) at nanoscale dimensions was made in 1998 at IBM Almaden Research Center in collaboration with researchers of Data Storage Systems Center (DSSC) – a National Science Foundation (NSF) Engineering Research Center (ERCs) at Carnegie Mellon University (CMU).

Heat-assisted magnetic recording (HAMR) is a magnetic storage technology for greatly increasing the amount of data that can be stored on a magnetic device such as a hard disk drive by temporarily heating the disk material during writing, which makes it much more receptive to magnetic effects and allows writing to much smaller regions.

<span class="mw-page-title-main">History of hard disk drives</span> Development of computer data storage

In 1953, IBM recognized the immediate application for what it termed a "Random Access File" having high capacity and rapid random access at a relatively low cost. After considering technologies such as wire matrices, rod arrays, drums, drum arrays, etc., the engineers at IBM's San Jose California laboratory invented the hard disk drive. The disk drive created a new level in the computer data hierarchy, then termed Random Access Storage but today known as secondary storage, less expensive and slower than main memory but faster and more expensive than tape drives.

Patterned media is a potential future hard disk drive technology to record data in magnetic islands, as opposed to current hard disk drive technology where each bit is stored in 20–30 magnetic grains within a continuous magnetic film. The islands would be patterned from a precursor magnetic film using nanolithography. It is one of the proposed technologies to succeed perpendicular recording due to the greater storage densities it would enable. BPM was introduced by Toshiba in 2010.

<span class="mw-page-title-main">James John Miles</span> English academic

James John Miles is a retired Professor of Computer Engineering in the School of Computer Science at the University of Manchester where he previously was head of the school and a member of the Nano Engineering & Storage Technology Research Group (NEST).

Exchange spring media is a magnetic storage technology for hard disk drives that allows to increase the storage density in magnetic recording. The idea, proposed in 2004 by Suess et al., is that the recording media consists of exchange coupled soft and hard magnetic layers. Exchange spring media allows a good writability due to the write-assist nature of the soft layer. Hence, hard magnetic layers such as FePt, CoCrPt-alloys or hard magnetic multilayer structures can be written with conventional write heads. Due to the high anisotropy these grains are thermally stable even for small grain sizes. Small grain sizes are required for high density recording. The introduction of the soft layer does not decrease the thermal stability of the entire structure if the hard layer is sufficiently thick. The required thickness of the hard layer for best thermal stability is the exchange length of the hard layer material. The first experimental realization of exchange spring media was done on Co-PdSiO multilayers as the hard layer which was coupled via a PdSi interlayer to a FeSiO soft layer.

<span class="mw-page-title-main">Yoshihiro Shiroishi</span>

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<span class="mw-page-title-main">Bruce Gurney</span> American physicist and inventor

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<span class="mw-page-title-main">Charles Denis Mee</span> British data storage engineer and author (1927–2023)

Charles Denis Mee was a British-American engineer, physicist, and author who was noted for his contributions in the areas of magnetic recording and data storage on hard disk drives (HDD). A large part of his career was with IBM in San Jose California. He is the author or editor of several books on magnetic recording.

<span class="mw-page-title-main">Two-dimensional magnetic recording</span>

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Robert E Fontana is an engineer, physicist, and author who is noted for his contributions in the areas of magnetic recording and data storage on hard disk drives (HDD) and on digital tape recorders. His work has concentrated on developing thin film processing techniques for nano-fabrication of magnetic devices including Giant Magnetoresistance read heads now used universally in magnetic recording. Much of his career was with IBM in San Jose, California. He is a Fellow of the Institute of Electrical and Electronics Engineers and a member of the National Academy of Engineering.

<span class="mw-page-title-main">Neal Bertram</span> American physicist, teacher, and author

Neal Bertram is a physicist noted for his contributions to the theory of magnetic recording. From 1968 to 1985, he worked for Ampex Corporation in Redwood City. From 1985 to 2004, he was an Endowed Chair Professor at the Center for Memory and Recording Research (CMRR), University of California at San Diego. He is the author of the book "Theory of Magnetic Recording". He is an elected Fellow of the Institute of Electrical and Electronics Engineers. In 2003, he won the IEEE Reynold B. Johnson Information Storage Systems Award.

<span class="mw-page-title-main">David Thompson (engineer)</span> American data storage engineer and inventor

David A. Thompson is an American electrical engineer and inventor with a long career at IBM. He is noted for his many contributions to magnetic recording technology. Thompson was inducted into the National Inventors Hall of Fame for the invention and development of the thin-film inductive head and the magnetoresistive read head. These heads are now ubiquitous in all hard-disk drives and magnetic tape recorders.

Albert Smiley Hoagland had a long career on the development of hard disk drives (HDD) starting with the IBM RAMAC. From 1956 to 1984, he was with IBM in San Jose, California, and then, from 1984 to 2005, he was the director of the Institute for Information Storage Technology at Santa Clara University. He wrote the first book on Digital Magnetic Recording. Hoagland played a central role in the preservation and restoration of the IBM RAMAC now displayed at the Computer History Museum, Mountain View, California. He died in Portland, Oregon, on 1 October 2022.

References

  1. 1 2 3 4 B. Gurney "Michael Mallary Receives 2013 Achievement Award", IEEE Magnetics Society Newsletter, Vol. 53, No. 1, p. 3, Jan. 2013
  2. 1 2 3 4 5 Computer History Museum: Oral History #102781590: Michael Mallary, June 19, 2019
  3. ↑ Mallary, Michael Leigh (1972). CP and the three pion decay of the K° (Thesis). California Institute of Technology. doi:10.7907/GVFN-DT58.
  4. ↑ Wood, Roger (2009). "Future hard disk drive systems". Journal of Magnetism and Magnetic Materials. 321 (6): 555–561. Bibcode:2009JMMM..321..555W. doi:10.1016/j.jmmm.2008.07.027.
  5. ↑ Researchgate: Scientific contributions: Robert E. Rottmayer
  6. ↑ M. Mallary, "Transducer with improved inductive coupling", US Patent 5184267, Oct 25, 1990
  7. ↑ P. Frank, "HDD Technology Roadmap", Information Storage Industry Consortium, Dec. 7, 2006
  8. ↑ Wood, R. (2000). "The feasibility of magnetic recording at 1 Terabit per square inch". IEEE Transactions on Magnetics. 36 (1): 36–42. Bibcode:2000ITM....36...36W. doi:10.1109/20.824422.
  9. ↑ Mallary, M.; Torabi, A.; Benakli, M. (2002). "One terabit per square inch perpendicular recording conceptual design". IEEE Transactions on Magnetics. 38 (4): 1719–1724. Bibcode:2002ITM....38.1719M. doi:10.1109/TMAG.2002.1017762.
  10. 1 2 M. Mallary, "Vertical magnetic recording arrangement", US Patent 4656546, Apr 7, 1987
  11. ↑ IEEE Magnetics Society: List of Fellows, 2007
  12. ↑ IEEE Magnetics Society Distinguished Lecturers 2009
  13. ↑ Justia Patents: Michael Mallary
  14. ↑ IEEE Xplore Author Profile: Michael Mallary
  15. ↑ Researchgate: Michael Mallary (list of publications)
  16. ↑ Plumer, Martin L; Van Ek, Johannes; Weller, Dieter, eds. (2001). The Physics of Ultra-High-Density Magnetic Recording. Springer Series in Surface Sciences. Vol. 41. doi:10.1007/978-3-642-56657-8. ISBN   978-3-642-62686-9.
  17. ↑ M. Mallary, "The Improbable Universe", Perseus Books, New York, 2004 ISBN 1-56858-301-X
  18. ↑ M. Mallary, "Our Improbable Universe", Youtube: Concorde Area Humanists, Apr 11, 2020
  19. ↑ M. Mallary, "The Improbable Universe: A Physicist Considers How We Got Here (2nd Edition)", CreateSpace Independent Publishing Platform, Feb 27, 2018 ISBN 1542597994
  20. ↑ M. Mortimer, "Book Review: Our Improbable Universe", Universe Today: Space and Astronomy News, Feb. 15, 2005
  21. ↑ M. Mallary, "Nuclear Power Can Mitigate Climate Change", Humanist Community Forum - Silicon Valley (on Vimeo), Sept. 23, 2012
  22. ↑ M. Mallary, "Nuclear Power, Debated", New York Times: Letters, Dec. 31, 2016
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