SANTA MARIA, Calif. —  A Nobel Prize (search)-winning physicist was sentenced Monday to two years in prison for killing a man and injuring seven other people while going more than 100 mph in his sports car.

John Robert Schrieffer, 74, a Florida State University (search) professor who taught at the University of California at Santa Barbara until 1991, pleaded no contest July 25 to vehicular manslaughter for crashing into a van last year.

Schrieffer had nine prior speeding tickets and was driving with a suspended license at the time. His attorney said the scientist fell asleep at the wheel of his Mercedes-Benz (search).

Under a plea bargain with prosecutors, Schrieffer was supposed to get eight months in the county jail. But Superior Court Judge Jim Herman decided otherwise after listening to tearful relatives of the crash victims during an August hearing.

"I think you need a taste of state prison," Herman said at the time. "The tragedy of this case is that you're a bright man who has made great contributions to society. ... It's a puzzle why you decided to drive high-performance cars at great speeds on public highways."

Colleagues had described Schrieffer earlier as a cautious person.

"This is not the Bob I worked with," said Brown University (search) professor Leon Cooper, who with Schrieffer and John Bardeen was awarded the Nobel in physics in 1972. "This is not the Bob that I knew."