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- Chai, Gaoda, et al.
(författare)
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Deciphering the Role of Chalcogen-Containing Heterocycles in Nonfullerene Acceptors for Organic Solar Cells
- 2020
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Ingår i: ACS Energy Letters. - : AMER CHEMICAL SOC. - 2380-8195. ; 5:11, s. 3415-3425
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Tidskriftsartikel (refereegranskat)abstract
- The field of organic solar cells has experienced paradigm-shifting changes in recent years because of the emergence of nonfullerene acceptors (NFAs). It is critically important to gain more insight into the structure-property relationship of the emerging A-DAD-A-type NFAs. In this Letter, a family of NFAs named BPF-4F, BPT-4F, and BPS-4F incorporating various chalcogen-containing heterocycles, i.e., furan, thiophene, and selenophene, respectively, was designed and synthesized. These NFAs exhibited dramatic differences in their photovoltaic performances with device efficiencies of 16.8% achieved by the thiophene-based cells, which was much higher than the furan-based ones (12.6%). In addition, the selenophene-based NFA showed a red-shifted absorption relative to the furan- and thiophene-based ones and obtained a decent efficiency of 16.3% owing to an improved J(SC). The reasons why these NFAs performed differently are systematically studied by comparing their optoelectronic properties and film morphology, which provides new understandings of the molecular design of high-performance NFAs.
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| 3. |
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| 4. |
- Wilzbach, Marco, et al.
(författare)
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Detecting neutral atoms on an atom chip
- 2006
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Ingår i: Fortschritte der Physik. - : Wiley-VCH Verlagsgesellschaft. - 0015-8208 .- 1521-3978. ; 54:8-10, s. 746-764
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Tidskriftsartikel (refereegranskat)abstract
- Detecting single atoms (qubits) is a key requirement for implementing quantum information processing on an atom chip. The detector should ideally be integrated on the chip. Here we present and compare different methods capable of detecting neutral atoms on an atom chip. After a short introduction to fluorescence and absorption detection we discuss cavity enhanced detection of single atoms. In particular we concentrate on optical fiber based detectors such as fiber cavities and tapered fiber dipole traps. We discuss the various constraints in building such detectors in detail along with the current implementations on atom chips. Results from experimental tests of fiber integration are also described. In addition we present a pilot experiment for atom detection using a concentric cavity to verify the required scaling.
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| 5. |
- Wilzbach, Marco, et al.
(författare)
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Simple integrated single-atom detector
- 2009
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Ingår i: Optics Letters. - : Optical Society of America. - 0146-9592 .- 1539-4794. ; 34:3, s. 259-261
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Tidskriftsartikel (refereegranskat)abstract
- We present a reliable and robust integrated fluorescence detector capable of detecting single atoms. The detector consists of a tapered lensed single-mode fiber for precise delivery of excitation light and a multimode fiber to collect the fluorescence. Both are mounted in lithographically defined SU-8 holding structures on an atom chip. Rb-87 atoms propagating freely in a magnetic guide are detected with an efficiency of up to 66%, and a signal-to-noise ratio in excess of 100 is obtained for short integration times.
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