Steven Chu (Chinese: 朱棣文; pinyin: Zhū Dìwén, born February 28, 1948) is an American physicist who is known for his research at Bell Labs and Stanford University in cooling and trapping of atoms with laser light, which won him the Nobel Prize in Physics in 1997, along with his scientific colleagues Claude Cohen-Tannoudji and William Daniel Phillips,.Chu served as the 12th United States Secretary of Energy from 2009 to 2013.