Chu sent a letter to department employees saying he wants to resume teaching and research, USA Today reported. He said he will go as soon as his successor has been confirmed by the Senate.
"As a Nobel Prize-winning scientist, Steve brought to the Energy Department a unique understanding of both the urgent challenge presented by climate change and the tremendous opportunity that clean energy represents for our economy," President Obama said in a statement. "And during his time as secretary, Steve helped my administration move America towards real energy independence."
Chu graduated from the University of Rochester and received a doctorate in physics from the University of California at Berkeley. The work that won him a Nobel Prize in physics was done at Bell Labs where he studied using lasers to trap and cool atoms.
In 1987, he joined the faculty of Stanford University and in 2004 moved to Berkeley, where he headed the Lawrence Berkeley National Laboratory and taught physics.