Digital holographic microscopy of highly sensitive living cells

In order to solve the problem that the existing living cell microscopy technology can not display the detailed information of cells, a high sensitivity digital holographic living cell microscopy technology is proposed in this paper. By measuring the phase distribution and refractive index distribution of living cells, the data of living cells are extracted and converted into digital hologram of living cells. Simulation and comparison of the commonly used two-dimensional living cell microscope methods. The experimental results show that the high-sensitivity digital holographic microscopic detection method can obtain the detailed information of living cells, which proves the effectiveness of this study.

Silicon-Based TM0-to-TM3 Mode-Order Converter Using On-Chip Shallowly Etched Slot Metasurface

Mode-order converters drive the on-chip applications of multimode silicon photonics. Here, we propose a TM0-to-TM3 mode-order converter by leveraging a shallowly etched slot metasurface pattern atop the silicon waveguide, rather than as some previously reported TE-polarized ones. With a shallowly etched pattern on the silicon waveguide, the whole waveguide refractive index distribution and the corresponding field evolution will be changed. Through further analyses, we have found the required slot metasurface pattern for generating the TM3 mode with high conversion efficiency of 92.9% and low modal crosstalk <−19 dB in a length of 17.73 μm. Moreover, the device’s working bandwidth and the fabrication tolerance of the key structural parameters are analyzed in detail. With these features, such devices would be beneficial for the on-chip multimode applications such as mode-division multiplexing transmission.