Professor Alan L. McWhorter. Photo: Courtesy of MIT Lincoln Laboratory
Alan L. McWhorter, a long-time professor in MIT’s Department of Electrical Engineering and Computer Science (EECS) and a division head and researcher at MIT Lincoln Laboratory, has died in New Orleans, Louisiana. He was nearly 88.
His family said his death was unexpected despite some recent health problems. A memorial service will be held at a later date.
McWhorter is best known for his research in electronic and quantum devices including transistors, lasers, and masers. In 1955, he developed the McWhorter model for low-frequency flicker (or 1/f) noise caused by surface effects in semiconductor devices. The model, sometimes called “the McWhorter effect,” continues to be widely cited today. In the mid-1960s, he received three patents related to semiconductors.
However, according to MIT faculty colleague Paul Penfield, Jr., his range of interests was broader and extended in many dimensions. “Al’s lesser-known but still pioneering work included aspects of control systems, power semiconductors, infrared detection, and optical communications,” said Penfield, an emeritus professor and former EECS department head. “But besides his technical breadth, he understood both the theoretical and experimental sides of engineering, cared about both the pedagogy and applications of various technologies, and promoted short-term applied research along with long-range curiosity-driven research.”
Penfield cites an example: “He was one of the few who appreciated the innovative formulation of electrodynamics developed by Professor Lan J. Chu in the late 1950s. This was easier to teach than the traditional formulations and models. But Al noted that the formula for force in magnetic materials was not physically reasonable. His persistent questioning led to some deep research by Professor Hermann Haus and me and eventually to a book resolving not only this issue, but others as well.”
A Long Legacy at MIT
Born in Crowley, Louisiana, on Aug. 25, 1930, McWhorter began his education in New Orleans at Tulane University’s School of Engineering, where he joined the Kappa Sigma fraternity. He transferred to the University of Illinois at Urbana-Champaign, receiving a bachelor’s degree in electrical engineering in 1951. He received an ScD degree in electrical engineering from MIT in 1955.
McWhorter joined the MIT Department of Electrical Engineering as an assistant professor in 1959, served as an associate professor from 1960 to 1966, and as a full professor for the next three decades. He had been a professor emeritus since 1996. During his time with EE (now EECS), he supervised more than 30 students’ work on their master’s, PhD, and ScD theses and served as a reader for about a dozen more. With a generous donation, he established a fellowship fund, the Alan L. McWhorter (1955) Fund, to support graduate students studying electrical engineering.
He was also affiliated with the Solid State Division at MIT Lincoln Laboratory for more than 40 years, beginning as a graduate student in 1951 and becoming a full staff member in 1955. He served as assistant head and associate head between 1962 and 1965, when he was named to head the division. A Lincoln Lab biography noted that, by the early 1970s, McWhorter was spearheading the division’s research programs on visible and infrared lasers and detectors: “Under his leadership, significant new research has been initiated on high-sensitivity infrared detectors and high-efficiency lasers suitable for satellite optical communications,” the biography states. McWhorter served as division head for 29 years, becoming a Lincoln Lab Fellow in 1994 and retiring in 1996.
“Al was a warm, generous and inspiring colleague,” recalled Erich Ippen, a principal investigator at MIT’s Research Laboratory of Electronics (RLE) and a professor emeritus of both electrical engineering and physics. “As an early leader in quantum electronics, he was a valuable mentor for us younger researchers in that area on campus as well as at Lincoln Lab.”
Frederick Leonberger knew McWhorter in both MIT roles. “I had the good fortune of having Al as my doctoral thesis advisor. His insightful guidance and high standards not only inspired me in my research, but also provided an excellent model for conducting and managing the research process,” said Leonberger, who is now a principal with EOvation Advisors. “At Lincoln Laboratory, where I subsequently worked, his leadership — as well as the range of research topics he had expertise in and contributed to — provided a role model of technical excellence for the staff, and helped enable the many important technical achievements of the Division over the years.”
McWhorter received his first two patents, both for semiconductor switching matrixes, in 1963 and 1964, at a time when researchers were experimenting with a variety of ways for using semiconductors in computers. The patents describe the development of the cryosar, one of the early semiconductor memory devices. Semiconductor memory (such as RAM) is now ubiquitous in electronics.
The third, and arguably most historically significant patent, came in 1966. It reflected McWhorter’s involvement as a member of one of three teams that had nearly simultaneously demonstrated the first semiconductor laser (then called an infrared maser). Today, semiconductor lasers are used in devices ranging from DVD players to laser pointers to printers to tattoo-removal devices.
In 1958, McWhorter and two colleagues received the National Electronics Conference Annual Award for their technical paper on solid-state masers.
McWhorter was also a long-time member of the IEEE, a leading technical professional organization. In 1968, he was named an IEEE Fellow, a distinction reserved for select members with extraordinary accomplishments. The IEEE recognized McWhorter “for contributions to control theory and its applications to switch power systems and image processing.” In 1971, McWhorter received the IEEE David Sarnoff Award, which recognizes exceptional work in electronics, “for outstanding contributions leading to a better understanding of semiconductor devices.” In 2000, he won an IEEE Third Millennium Medal “for contributions to control theory and its applications to switch power systems and image processing.” He was one of just 45 members of the IEEE Electron Devices Society to be so honored.
In 1993, McWhorter was elected to the National Academy of Engineering for “outstanding research and technical leadership in the fields of quantum electronics and solid-state devices.” He was also a long-time fellow of the American Physical Society and a member of the scientific and engineering societies Sigma Xi, Tau Beta Pi, and Eta Kappa Nu (HKN).
Among other professional activities, McWhorter was an associate editor of the IEEE Transactions on Electronic Devices and a member of the editorial board for the Proceedings of the IEEE. During his career, he authored or co-authored dozens of scientific articles and hundreds of reports and contributed to several books.
A Life-Changing Challenge
On March 29, 1969, McWhorter was involved in a near-fatal head-on collision on Route 2 in Arlington, Massachusetts, an accident so devastating that former colleagues recalled it well nearly 50 years later. A 1971 article in the MGH News, a Massachusetts General Hospital newsletter, described the scenario this way: “A team of residents and interns huddled over Professor McWhorter in a small room inside the MGH Emergency Ward. What they — and the X-rays — saw was to challenge a battery of some of the world’s most skilled medical experts over the next four months.”
McWhorter sustained what the hospital called “total body crush,” including a skull fracture, a concussion, facial injuries, and broken bones in his arms, legs, shoulder, and hip. At one point, he needed a respirator due to lung problems caused by fractured ribs; at another, he required emergency surgery for a ruptured spleen. For weeks, a gravely high fever, which once spiked at 106 degrees, threatened his life; he also spent several months on a feeding tube. He lost his right eye due to irreparable damage, but an eye specialist from the Massachusetts Eye and Ear Institute managed to save the left one.
Yet, as the MGH newsletter puts it, after seven operations and multiple setbacks, McWhorter “walked out of the MGH on July 22,” and returned to work at MIT a few weeks later. Following the accident, he went back to his favorite pursuits, including traveling and exploring other cultures — for instance, reading scientific treatises in Russian. He also returned to hiking and mountain-climbing, beginning with a trip to the Grand Tetons one year after his release from MGH.
After retiring, McWhorter returned to the New Orleans area and began participating again in Tulane activities, such as the Friends of Music, the Summer Lyric Theatre, and the Emeritus Club & Educational Conference offerings of the Alumni House. Along with his brother Andrew, he became re-involved with Kappa Sigma, working to refinance and repair the fraternity house and honor outstanding alumni. The brothers contributed to a fund to endow a Kappa Sigma scholarship at Tulane. After Andrew McWhorter’s death in 2008, the scholarship was renamed in Andrew’s honor.
Alan McWhorter, who died on July 11, 2018, is survived in the New Orleans area by niece Patricia McWhorter (Peter C. Broussard); nephews David McWhorter (Lisa) and Steven McWhorter (Renee), and six grandnieces: Olivia Broussard (Lucien Weiss); Allyson McWhorter; Brindley McWhorter; Rebecca McWhorter Ruegge (Gene); Elizabeth McWhorter Guillory (Dakota); and Emily McWhorter Menendez (Colin).
Gifts in memory of Alan McWhorter may be made to MIT for the Alan L. McWhorter (1955) Fund, account #3304350. Credit-card gifts can be made using the following link: https://giving.mit.edu/alan-mcwhorter. Checks should be made payable to MIT and mailed to: MIT Memorial Gifts Office, 600 Memorial Drive, Room W98-500, Cambridge, MA 02139.
For another version of this story, with an additional historic photo, please visit the MIT News website.