{"id":59258,"date":"2014-05-13T09:11:49","date_gmt":"2014-05-13T13:11:49","guid":{"rendered":"https:\/\/www.ucf.edu\/news\/?p=59258"},"modified":"2022-12-09T13:17:34","modified_gmt":"2022-12-09T18:17:34","slug":"ucf-scientist-gets-three-big-journal-hits-one-year","status":"publish","type":"post","link":"https:\/\/www.ucf.edu\/news\/ucf-scientist-gets-three-big-journal-hits-one-year\/","title":{"rendered":"UCF Scientist Gets Three Big Journal Hits in One Year"},"content":{"rendered":"
海角直播 physicist Zenghu Chang has done it again. For a third time this year, his research group has published an article in a Nature journal.<\/p>\n
This time, Chang and his team have developed a new ultrafast light source for observing electron motion in molecules \u2013 made up of nuclei and electrons \u2013 at the point before the nuclei start to move. By being able to observe what actually happens, scientists can begin to understand how an electron interacts with other electrons, which may help improve the efficiency of solar cells.<\/p>\n
\u201cThe charge migration that theorists have been predicting since 1999 happens so quickly we haven\u2019t been able to observe it yet,\u201d Chang said. \u201cIt\u2019s very exciting, because we have found a new way to build light sources that may allow us to see it in the future.\u201d<\/p>\n
Being able to see this superfast interaction between electrons gives scientists another tool to unlock the rules that govern the quantum-mechanics world \u2013 a world where microscopic objects don\u2019t obey the laws of physics we have come to rely on for understanding in the macro world.<\/p>\n
So how did Chang and his team manage to develop the new light source? The team borrowed an idea from Chang\u2019s earlier innovative work<\/a> in the area of ultrafast lasers.<\/p>\n \u201cWe control the below-threshold harmonic light emission by using electromagnetic fields with time-dependent ellipticity, like we have done to the above-threshold high-order harmonics,\u201d said Chang referring to the creation of a 67-attosecond pulse of extreme ultraviolet light, which earned him international recognition.\u00a0 \u201cWe thought: Could we use the same gating fields to show the dependence of the below-threshold harmonic intensity on the carrier-envelope phase of the driving laser? It took us some time to find the right experimental parameters, but the answer is yes.\u201d<\/p>\n