Supplementary MaterialsSupplementary Information srep21091-s1. excitation wavelength or the excitation power density. The phenomenon of photon cascade emission or the so called quantum cutting, in which a photon of high energy is absorbed and converted to two or more photons with lower energies, has been studied intensively in the past few decades because of its potential applications in mercury-free lamps and plasma display panels1,2,3,4,5,6,7,8,9. In recent years, this phenomenon has drawn great attention in the research and development of high-efficiency solar cells because it can significantly improve the conversion efficiency of photon to Rabbit Polyclonal to MDC1 (phospho-Ser513) electricity and reduce heat generation10,11,12,13. Owing to their unique energy states, rare-earth ions, especially the lanthanide ions, are considered as promising candidates not only for photon up-conversion but also for photon down-conversion13,14,15,16,17,18,19,20,21,22. For example, solid state full color display23 has been demonstrated by exploiting the photon up-conversion in three lanthanide ions of Pr3+, Er3+, and Tm3+. In addition, the lanthanide ions have exhibited fascinating luminescent properties such as intense narrow-band emission, high conversion efficiency, broad emission peaks, much different lifetimes, and good thermal stability8,21,24,25,26,27. Therefore, rare-earth-ion-doped materials have been widely studied BGJ398 reversible enzyme inhibition and exhibited potential application in the fields of illumination, imaging, display, solar cells, and medical radiology because such materials can be fabricated at a BGJ398 reversible enzyme inhibition low cost and in large quantities23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44. In rare-earth-ion-doped materials, Tb3+-doped glasses have been the focus of many studies because of their high luminescence efficiency at around 550?nm which is convenient for direct coupling with silicon detectors45. More interestingly, it has been shown that the luminescence can be further enhanced by adding Gd3+ into Tb3+-doped glasses because of the energy transfer (ET) from BGJ398 reversible enzyme inhibition Gd3+ to Tb3+, as schematically shown in Fig. 1. In fact, the ET between Gd3+ and Tb3+ has been extensively investigated in many other different host materials46,47,48,49,50. Although electrons can be produced in Gd3+, the luminescence from Gd3+/Tb3+-codoped eyeglasses arises primarily from the transitions from the particular level 5D4 to the amounts 7F0C6 in Tb3+ which bring about four emission bands in the noticeable light area46,47,48,49,50. In Fig. 1, it really is pointed out that the amounts 6GJ in Gd3+ can be found well above the high-energy amounts in Tb3+ (5K7 etc.) as the levels 6DJ, 6IJ, and 6PJ in Gd3+ have comparable energies with some energy in Tb3+. If the populace of the amounts 6GJ in Gd3+ can be induced, you can anticipate the transitions of electrons to the low-energy amounts (6DJ, 6IJ, and 6PJ) of BGJ398 reversible enzyme inhibition Gd3+, the ET of electrons from Gd3+ to Tb3+, the transitions of electrons to the particular level 5D4 and lastly to the amounts 7F0C6. Such a cascade changeover process may bring about the cascade emission of photons with different energies. Used, the populace of the amounts 6GJ in Gd3+ could be realized through the use of femtosecond (fs) laser beam light at ~400?nm through two-photon-induced absorption (TPA). The high peak power and wide linewidth of fs laser beam light are extremely ideal for effectively thrilling the levels 6GJ in Gd3+. In fact, fs laser beam light at 800?nm has been used to excite the three-photon-induced luminescence in rare-earth-ion-doped eyeglasses37. When fs laser beam light at 400?nm can be used to excite the amounts 6GJ in Gd3+, the particular level 5D3 in Tb3+ with a wavenumber of ~26336?cm?1 (corresponding to a wavelength of ~381?nm) may also be populated through Rabi oscillation or phonon-assisted transition51, resulting in the traditional emission from Tb3+. For excitation wavelengths (Managing the Two-Photon-Induced Photon Cascade Emission in a Gd3+/Tb3+-Codoped Cup for Multicolor Screen. em Sci. Rep. /em 6, 21091; doi: 10.1038/srep21091 (2016). Supplementary Material Supplementary Info:Just click here to see.(3.6M, pdf) Acknowledgments The authors acknowledge the monetary support from the National Organic Science Basis of China (Grant Nos. 51171066, 11374109, and 11204092) and the Scientific Study Basis of the Graduate College of South China Regular University (Grant No. 2015lkxm01). Footnotes Writer Contributions S. Lan and M.-H. Yuan conceived the theory. S.-L.Tie and Z.-M. Yang fabricated the cup samples. M.-H. Yuan, H.-H. Lover, and H. Li completed the optical experiments. S. Lan, M.-H. Yuan, S.-L. Tie, and Z.-M. Yang analyzed the info. M.-H. Yuan and S. Lan wrote the manuscript. S. Lan and S.-L. Tie supervised the task. All of the authors examine and commented on the manuscript..