Abstract A novel tunable comb filter composed of a single-mode/multimode/polarization-maintaining-fiber-based Sagnac fiber loop is proposed and experimentally demonstrated. The filter tunability is achieved by rotating the polarization controller. The spectral shift is dependent on rotation direction and the position of polarization controller. In addition, the adjustable range achieved by rotating the half-wave-plate polarization controller is twice higher than that of the quarter-wave-plate one.
Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 11274181, 10974100, and 10674075), the Tianjin Key Program of Application Foundations and Future Technology Research Project, China (Grant No. 10JCZDJC24300), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120031110033).
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.