Igor Alexeff, age 81, of Oak Ridge, passed away on Oct. 25, at his home in Oak Ridge.

He had been diagnosed with ALS in March of this year, and chose to spend his time with his wife and partner of 58 years, Anne, in the home that they had shared for over 40 years. Anne was at his side when he passed.

Igor was preceded in death by his father, Alexander Alexeff, in 1976, and by his mother, Tamara Tchirkow Alexeff, in 1987.

He is survived by his wife, Anne; son, Alexander Alexeff, and daughter-in-law, Monika Dimmel-Alexeff, both of Malibu, Calif.; daughter, Helen Alexeff, of Knoxville; and granddaughters, Zoe, Ivy, and Noa Alexeff, of Malibu, and Jasmine Alexeff-Little, of Knoxville.

Igor was born in Pittsburgh, Pa., in 1931, and had a lifelong enthusiasm and talent for theoretical mathematics, experimentation, and invention. At the age of 17, he was one of 40 finalists selected to present their projects in Washington for the annual Science Talent Search, which drew over 16, 000 contestants from across the nation. He was awarded a scholarship, and finished in the Top 12.

Later, he was awarded a full college scholarship, and he chose to attend Harvard University, where he graduated with honors with a bachelor’s degree in physics in 1952. He received his doctorate in nuclear physics from the University of Wisconsin in 1959, followed by a postdoctoral fellowship from the National Science Foundation, which he chose to complete at the University of Zurich in Switzerland.

After completing his post-doctorate work, he was offered a position at Oak Ridge National Laboratory, where he worked on controlled thermonuclear fusion, until 1970, when he decided to become a professor. He accepted a position with the University of Tennessee in the electrical engineering department, where he taught and worked in industrial plasma engineering.

Igor retired from teaching in 1996, but he retained his office and research lab, and continued his work, until 2011.

He was co-founder of the IEEE NPSS, and a lifetime fellow of the IEEE, and fellow of APS. He has over 100 refereed publications and over 10 patents. He accepted numerous invitations as visiting professor, and spent extended periods in Japan, India, South Africa, and Brazil. His love of travel and adventure was shared by his wife, Anne, and together they travelled the world. He is greatly missed.

The family will receive friends 6-8 p.m. Monday at Weatherford Mortuary in Oak Ridge, with the service to follow at 8. In lieu of flowers, the family requests that donations be made to the MDA and towards ALS research.