ABSTRACT
In this paper, an optical waveguide evanescent field fluorescence microscopy is studied. Based on Maxwell's equation, a seven-layer theoretical analysis model is developed for the evaluation of an optical waveguide excitation fluorescence microscopy. The optical waveguide excitation fluorescence microscopy structure is systematically and comprehensively analysed at the wavelengths of 488, 532 and 646 nm for fluorescent dyes. The analysis results provide some useful suggestions, which will be beneficial to the research of an optical waveguide evanescent field fluorescence microscopy.
ABSTRACT
An optical waveguide cantilever system with a tip is introduced as the displacement detection system of chip-based atomic force microscopy (AFM) system. A chip-based AFM on optical waveguide is demonstrated with sensitivity of up to 4.0 × 10-2 nm-1 , which is mainly constructed by a 210 nm thick optical waveguide cantilever with a nano-tip. The nano-tip is a height of 1.2 µm and diameter of 140 nm. This integrated on-chip system provides a displacement range of approximately ±0.4 µm, which makes it possible for the device to be used for AFM imaging and pays the way for further performance improvement.
ABSTRACT
This paper reports a non-coplanar misalignment optical waveguide cantilever sensor realizing a monotonic response with a large operation range. A 1×2 Y-branch optical power splitter cantilever structure was designed, and one of the branches was reduced in thickness at the end, as a non-coplanar structure with respect to another. The misalignment coupling of the two branches due to the thickness of one branch leads to a monotonic response of an optical waveguide cantilever sensor. The simulation results showed a monotonic response with a sensitivity of 6×10-4 n m -1 in a large operation range of -1 to 1 µm.
ABSTRACT
This study focuses on re-examining the early 2000s hiatus and the associated key components of the global mean surface temperature (GMST) using multiscale statistics for five well-known gridded surface temperature and two reanalysis datasets. The hiatus is characterized as a near-zero trend on the decadal scale corresponding to the maximum P-value via an F-test in statistics. The results reveal that the hiatus exists in both the GMST and global mean air temperature (GMAT) time series, rather than in global warming component, which has maintained an approximately constant rate of change of approximately 0.08 °C/decade over the past three decades. The hiatus's duration is different from that of time series such as 2002-2012/2001-2013/2002-2014 in HadCRUT4, NOAA-old, ERA-Interim and NCEP-R2. The newly gridded datasets with data infilling or bias correction for interpreting the sea surface temperature (SST) measurement from the old versions show a slightly higher trend from 2002-2012 than the hiatus, which is thus regarded as a slowdown. Comparison suggests that the hiatus should be during the period 2002-2012. Orthogonal wavelet decomposition of the temperature time series shows that the hiatus was merely a decadal balance between cooling from interannual variability and global warming, in addition to weak warming from interdecadal and multidecadal climate oscillations. In addition, the evolutions of the GMST's interannual composites are well coincided with Niño3.4 SST anomalies, which is consistent with the numerical simulation performed by Kosaka and Xie in 2013. Hence, it is the anomalous El Niño Southern Oscillation (ENSO) events in the early 2000s that caused the hiatus despite a constant rate of global warming and the maximum magnitude of the multidecadal composite that led to the limited contribution to the trend during this period. The multidecadal composite follows a downward path, which implies that future climate conditions will likely rely on competition between multidecadal cooling and global warming if the multidecadal climate cycle repeats, as was experienced during the second half of the twentieth century.
