Acoustical Society of America
Biennial Award - 1970

Logan E. Hargrove

Logan E. Hargrove, born in Spiro, Oklahoma, has impacted strongly on at least two other states—Michigan and New Jersey. He received BS and MS degrees in Physics from Oklahoma State University in 1956 and 1957, respectively, and the PhD in Physics from Michigan State University in 1961. He joined Warren Mason and his co-workers at Bell Telephone Laboratories in September 1962. In 1964, he married Sandra Hamilton.

Dr. Hargrove is a Fellow of the Acoustical Society of America and a member of the Optical Society of America.

Logan began doing physics research in his junior year at Oklahoma State under George B. Thurston, and continued under his guidance to obtain the MS degree. Among the honors Logan earned at Oklahoma State are election to the physics honor society, Sigma Pi Sigma; to Sigma Xi; to the bandsman's honorary, Kappa Kappa Psi; and to the leadership honorary, Omicron Delta Kappa. Active in student affairs, he served as President of the Student Council for the School of Arts and Sciences, Chapter President of Sigma Pi Sigma, and among other activities found time to serve as Publicity Chairman for the marching band.

At Michigan State, under the tutelage of the late Professor Hiedemann, Logan became an expert on the diffraction of light by ultrasonic waves. With his optical experience, it should surprise no one that he quickly became interested in a powerful new tool—the laser. In 1963—1964, Logan conceived and carried out the first experiments that demonstrated mode-locking (stabilization of the amplitude and frequency of the axial modes of a laser) by an ultrasonic-standing-wave light modulator placed inside the optical cavity. The effect produced is coupling of the optical cavity modes to produce intense, short, and periodic optical pulses. This work resulted in a dramatic reduction of the then-available laser pulse duration, and is widely recognized as a significant contribution. The mode-locking principle has since been used to accomplish even further reductions in pulse duration. Logan has been granted a basic mode-locking patent. Logan's publications make both theoretical and experimental contributions. He has produced numerous papers elucidating the intricacies of the diffraction of light by ultrasonic waves. His most recent papers deal with frequency shifting of mode-locked laser pulses and with interferometric combinations of such pulses. All of Logan's work is a model of meticulous precision and an inspiration to his associates.

In 1965, the Society of Motion Picture and Television Engineers awarded Logan an Honorable Mention Citation for a paper, co-authored with J. S. Courtney-Pratt, on "Some Photographic Studies of the Light Output of an Intracavity-Modulated Gas Maser."

Logan's creative talents have not been confined to the laboratory. One of his experiments with a voice-controlled visual display was expanded on by artist Robert Rauschenberg, with Logan consulting, in the construction "Soundings" which toured Europe in 1968 and was subsequently on display in the Museum of Modern Art in New York. He has also indulged in wood-carving, painting, photography, cabinet-making and finishing, and other hobbies of a creative–artistic nature. Some of the results of his projects can be seen in his home, which is beautifully furnished with many of his own creations.

Logan likes variety. His attitude is revealed by an exchange that took place after I had bought a ladder, an item which he needed also. I was so insensitive as to suggest that with his tools and know-how, he could very quickly make a ladder that would be both better and cheaper than any I had seen on the market. While generously conceding that it might be fun to fit the first rung, Logan's response made it clear that the whole job seemed too repetitious to be his kind of project.

Some unusual items that can be seen in Logan's home are parts of his Indian dance costume that dates back to his years in the Boy Scouts and the Order of the Arrow. He participated in a group that traveled about the country presenting a program of Indian dances in costumes made by the boys themselves—costumes that had to withstand the rigors of the dance, of course. If the bit of Cherokee that Logan boasts in his ancestry gave him an advantage in these endeavors, it is hardly a crucial one. As shown by many examples, it is typical of Logan that whatever he tackles, he tackles well.

Typical also is his helpfulness. When approached, he always takes time first to make sure that he understands the problem—that he knows what is wanted so that his comments will be relevant. This is true whether in the realm of recommending a restaurant, discussing the problems of house buying, giving advice on home improvement and landscaping projects, or consulting in his technical specialties. Logan's helpfulness often extends beyond merely giving advice. As an example may be cited the actual work of carefully digging away the dirt that a contractor had filled in around a friend's tree.

Today an appreciative and enthusiastic attendee of the performing arts, Logan was once a performer himself when he played baritone in the concert and marching bands in high school and at Oklahoma State. It is safe to bet that he positioned himself in precisely the right place at the right time (while playing the right note!) in every formation. His election to Kappa Kappa Psi, noted above, testifies to the quality of his performance.

On the Chinese calendar—and the Hargrove's—this is the Year of the Dog! If you wonder what happens when 90 pounds of energetic, rambunctious Weimaraner puppy lives with you. Sandy and Logan can fill you in on some of the hilarious details. Having in view Logan's outstanding successes in everything else he ever attempted (he even succeeded in quitting smoking!), we can presume that Doctor Duff, now enrolled in Advanced Obedience, will be an exceptionally well-trained dog—eventually. In the meantime, the happening is fun.

ROBERT N. THURSTON