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21.
Since the quality factor of an acoustic wave resonator (AWR) reached 1011, AWRs have been regarded as a good carrier of quantum information. In this paper, a scheme to construct a NOON state with two AWRs assisted by a nitrogen‐vacancy‐center ensemble (NVE) is proposed. The two AWRs cross each other vertically, and the NVE is located at the center of the crossing. By considering the decoherence of the system and using resonant interactions between the AWRs and the NVE, and the single‐qubit operation of the NVE, a NOON state can be achieved with a fidelity higher than 98.8% when the number of phonons in the AWR is . 相似文献
22.
《Current Applied Physics》2019,19(9):984-986
A highly symmetric ZnO micro-fence is prepared to form an optical resonator, which a symmetric array consisting of six elongated hexagonal microcolumns. It is found that the luminescence emission could be enhanced at the edge of ZnO micro-fence and the wavelength dependent light intensity could be influenced by its geometry. The optical characterization along with theoretical calculations and computer simulation analysis suggest that the Fabry-Perot and Cross-whispering gallery modes are generated in ZnO micro-fence. The individual ZnO micro-fence can regarded as an optical resonator structure. Furthermore, it is proposed that the source concentration around the substrate during the growth is a crucial factor for forming such a micro-fence. 相似文献
23.
A communication system is implemented on digital signal processors (DSPs) for the underwater acoustic environment. The implemented receiver uses time reversal multi-channel combining followed by a single-channel decision feedback equalizer. Periodic channel estimation is employed to track the channel fluctuations. These techniques are used to mitigate time-varying inter-symbol interference, which is the main challenge in the underwater acoustic channel at operating frequencies greater than 10 kHz. Various optimization tasks are performed to reduce the receiver computational complexity. A fast implementation of the matching pursuit algorithm is tested on the DSP platform. Its performance, in terms of accuracy and run-time, is compared with that of the basic matching pursuit algorithm. Experimental results of the transmission and demodulation of binary phase-shift keying signals at three different symbol rates were obtained in the local Delaware Bay. The low bit error rates demonstrate the effectiveness of our implementation. 相似文献
24.
By taking the coupling effect into consideration, we study the resonance condition of a photonic wire microring resonator (PWRR) sensor and compare our results with the previous work. Simulation results show that the resonant wavelength and sensitivity strongly depend on the coupling strength. The difference caused by the coupling effect can be up to tens of nanometers for the resonant peak position and tens of nm/RIU for the sensitivity in a silicon-on-insulator (SOI) PWRR. Such a giant influence from coupling effect cannot be disregarded and should be considered seriously for the design and application of PWRRs. It also shows an alternative tuning technique by controlling the coupling strength. 相似文献
25.
提出由T型空腔和挡板组成的两种金属-电介质-金属(MIM)波导结构,分别为:正T型空腔结构和倒T型空腔结构,并应用有限元法系统地研究了该结构的透射特性.对于正T型空腔结构,仿真结果出现了双重法诺共振现象,并且共振波长可以通过改变T型空腔长度和高度进行调节.该结构有助于设计成敏感度达到1 620nm/RIU、品质因数为5.4×10~4的纳米传感器.对于倒置T型空腔,在波导中产生了多重法诺共振现象,其敏感度可达1 560nm/RIU,品质因数为9.37×104.该结构有望在光学集成回路,特别是纳米传感器、光束分路器方面具有广泛应用. 相似文献
26.
以离子液体溴化(1-己基-3-甲基咪唑盐)作为电解质和掺杂剂采用电化学一步法制备了微纳米复合结构的聚(3,4-乙烯基二氧噻吩)薄膜,薄膜由槽内排布着纳米珠链的棒状结构组成. 研究表明,通过控制电流密度的大小,可以调节棒状结构和珠状结构的平均直径. 离子液体中的咪唑阳离子和对阴离子均掺杂到聚合物中,该薄膜具有可逆的电化学活性及水下超疏油特性. 相似文献
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