1 School of Electronic Information Engineering, Tianjin University of Technology, Tianjin 300384, China; 2 Key Laboratory of Film Electronic and Communication Device, Engineering Research Center of Communication Devices of Ministry of Education, Tianjin 300384, China
Abstract In this paper, we propose a scheme for photon echo chirped detection process composed of additional modulation pulses to obtain controllable geometric phase. The geometric phases are observed and measured by a beat signal between the photon echo field and the chirped field. The chirped detection model reveals that the period of the beat signal increases as the chirped rate and delay time increase. Additionally, a two-fold relationship between the modulation phase and the echo shift phase is obtained. The numerical simulations accord with the theoretical results obtained by the finite difference time domain (FDTD) method.
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.