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With the ultra-thin thickness and excellent performance, metalens are bi-dimensional optical elements composed of nanopatterned structures that demonstrate significant potential for various applications such as holography, planar imaging and tomography. However, the small size of metalens makes it challenging to precisely quantify their wavefront aberration, thus impeding their broader utilization. To address this challenge, we propose an innovative method for measuring wavefront aberration in metalens using phase-shift interferometry. Furthermore, we have developed the Small Aperture Interferometric Imaging Detection System with variable fields of view, specifically designed for metalens. This system can accurately measure the wavefront aberration of metalens with different fields of view with PV accuracy of 1/20λ, further enabling the acquisition of imaging performance parameters, including Modulation Transfer Function (MTF) and Point Spread Function (PSF). This innovative measurement approach not only enables quantitative evaluation of performance of metalens but also assists designers and manufacturers in optimizing process flows and identifying potential defects. As a result, this approach aids in promoting the industrial application of metalens.

With the ultra-thin thickness and excellent performance, metalens are bi-dimensional optical elements composed of nanopatterned structures that demonstrate significant potential for various applications such as holography, planar imaging and tomography. However, the small size of metalens makes it challenging to precisely quantify their wavefront aberration, thus impeding their broader utilization. To address this challenge, we propose an innovative method for measuring wavefront aberration in metalens using phase-shift interferometry. Furthermore, we have developed the Small Aperture Interferometric Imaging Detection System with variable fields of view, specifically designed for metalens. This system can accurately measure the wavefront aberration of metalens with different fields of view with PV accuracy of 1/20λ, further enabling the acquisition of imaging performance parameters, including Modulation Transfer Function (MTF) and Point Spread Function (PSF). This innovative measurement approach not only enables quantitative evaluation of performance of metalens but also assists designers and manufacturers in optimizing process flows and identifying potential defects. As a result, this approach aids in promoting the industrial application of metalens. [ABSTRACT FROM AUTHOR]

The SPR phenomenon results in an abrupt change in the optical phase such that one can measure the phase shift of the reflected light as a sensing parameter. Moreover, many studies have demonstrated that the phase changes more acutely than the intensity, leading to a higher sensitivity to the refractive index change. However, currently, the optical phase cannot be measured directly because of its high frequency; therefore, investigators usually have to use complicated techniques for the extraction of phase information. In this study, we propose a simple and effective strategy for measuring the SPR phase shift based on phase-shift interferometry. In this system, the polarization-dependent interference signals are recorded simultaneously by a pixelated polarization camera in a single snapshot. Subsequently, the phase information can be effortlessly acquired by a phase extraction algorithm. Experimentally, the proposed phase-sensitive SPR sensor was successfully applied for the detection of small molecules of glyphosate, which is the most frequently used herbicide worldwide. Additionally, the sensor exhibited a detection limit of 15 ng/mL (0.015 ppm). Regarding its simplicity and effectiveness, we believe that our phase-sensitive SPR system presents a prospective method for acquiring phase signals.

Abstract: For the long-term assessment of CO2 geological sequestration, the dissolution rate of feldspar was measured under various degrees of saturation based on observations of the time-course change of dissolved crystal surfaces on a nanoscale. We identified that the dependence of solution saturation state on anorthite dissolution rate follows to a L-shaped function, rather than to a linear function. Compared with a linear assumption, such a nonlinear form provides a much lower estimate of dissolution rate. This implies that the difference of rate formula can cause meaningful errors in the timescale evaluation of various geochemical processes. In this study, therefore, the effect of the function form of dissolution rate was also checked using the geochemical simulation code to analyze CO2 geological sequestration. [Copyright &y& Elsevier]

The SPR phenomenon results in an abrupt change in the optical phase such that one can measure the phase shift of the reflected light as a sensing parameter. Moreover, many studies have demonstrated that the phase changes more acutely than the intensity, leading to a higher sensitivity to the refractive index change. However, currently, the optical phase cannot be measured directly because of its high frequency; therefore, investigators usually have to use complicated techniques for the extraction of phase information. In this study, we propose a simple and effective strategy for measuring the SPR phase shift based on phase-shift interferometry. In this system, the polarization-dependent interference signals are recorded simultaneously by a pixelated polarization camera in a single snapshot. Subsequently, the phase information can be effortlessly acquired by a phase extraction algorithm. Experimentally, the proposed phase-sensitive SPR sensor was successfully applied for the detection of small molecules of glyphosate, which is the most frequently used herbicide worldwide. Additionally, the sensor exhibited a detection limit of 15 ng/mL (0.015 ppm). Regarding its simplicity and effectiveness, we believe that our phase-sensitive SPR system presents a prospective method for acquiring phase signals. [ABSTRACT FROM AUTHOR]

A Stroboscopic phase-shift interferometry has been developed to visualize surface acoustic wave (SAW) propagation on SAW devices quantitatively. The developed interferometry is a Fizeau-type one with a multi-mode semiconductor laser diode and an optical isolator. With the laser light illuminating stroboscopically, observed interference intensity gives information about average displacements of the vibrations. Fifty MHz SAW propagation on the surface of the SAW device has been measured with the interferometry. Distribution of the SAW along the propagation path has been observed, whose amplitude is 3 nm (p-p). Repetition accuracy evaluated with the root mean square method is 1/2500 of the laser wavelength. The system is useful for estimating and improving performances of micro-devices. [ABSTRACT FROM AUTHOR]

The Gibbs free energy change, ΔGr, dependence of the anorthite dissolution rate in a supercritical CO2-water system was measured as part of a geochemical assessment of CO2 geological sequestration. Being bounded at ΔGrcrit, the critical ΔGr required for an opening of the etch pit at a screw dislocation, it has been accepted that mineral dissolution follows etch pit formation assisted by dislocations below ΔGrcrit, whereas the horizontal step retreats without the etch pit above ΔGrcrit. The experiment described herein, however, revealed that another mode of dissolution occurs more distant from equilibrium by spontaneous formation of the etch pit over the entire surface, as observed on calcite. The dissolution rate is higher by more than one order of magnitude than that in the dislocation-assisted mode. Therefore, including the rate gap at ΔGrcrit, a nonlinear curve with three steps instead of a sigmoidal curve is proposed for the ΔGr dependence of the anorthite dissolution rate. Extremely slow rates were observed depending on observed points for the same ΔGr condition. Although the reason for such a rate difference remains unknown, it is likely related to the defect density on the crystal surface. It is possible that initial spreading of the dissolved surface attributable to the etch pit formation assisted by defects provides some trigger for subsequent explosive etch pit formation. These findings suggest that the initial transient process can strongly influence the kinetics of geochemical reactions that occur during CO2 geological sequestration. [ABSTRACT FROM AUTHOR]