Zernike phase contrast has been added to a full-field X-ray microscope with Fresnel zone plates that was in operation at 6.95 keV. The spatial resolution has also been improved by increasing the magnification of the microscope objective looking at the CsI(Tl) scintillation crystal. Cu no. 2000 meshes and a zone plate have been imaged to see the contrast as well as the spatial resolution. A Halo effect coming from the Zernike phase contrast was clearly visible on the images of meshes.
To overcome the limitations of phase sampling points in testing aspherical surface wavefronts using traditional interferometers, we propose a high-spatial-resolution method based on multi-directional orthogonal lateral shearing interferometry. In this study, we provide a detailed description of the methodology, which includes the theoretical foundations and experimental setup, along with the results from simulations and experiments. By establishing a relational model between the multi-directional differential wavefront and differential Zernike polynomials, we demonstrate high-spatial-resolution wavefront reconstruction using multi-directional orthogonal lateral shearing interferometry.
MOE Key Laboratory of TianQin Mission, TianQin Research Center for Gravitational Physics and School of Physics and Astronomy, Frontiers Science Center for TianQin, Gravitational Wave Research Center of CNSA, Sun Yat-sen University (Zhuhai Campus), Zhuhai, 519082, China.
As a critical payload of the gravitational wave detection interferometry system, the tilt-to-length (TTL) noise has a significant influence on the detection accuracy of the interferometry system. The non-geometric TTL (NG-TTL) noise, which is the main component of the TTL noise within the telescope, is closely related to the sensitive aberrations of the system's small pupil. Due to the different environments of the earth and space, structural deformations of the telescope can cause significantly unfavorable changes in the sensitive aberrations at the small pupil.
Microscopes generally achieve better 2D imaging compared to 3D, and super-resolution microscopes often aggravate such axial-lateral resolution mismatch. A prime example is vortex phase-based stimulated emission depletion (STED) fluorescence microscopy, which only narrows the point-spread function laterally, thereby increasing the point-spread function (PSF) anisotropy. In this study, we developed a semi-analytical theory based on the Nijboer-Zernike expansion, developed a set of metrics and performed experiments to establish the merits of the alternative, bivortex phase-based, coherent-hybrid STED.
We introduce a concept of aberration correction under microscopy that is based on observation of circular Brownian motion of an object driven by orbital angular momentum of a Laguerre-Gaussian (LG) beam. Following the concept, we establish an aberration-correction scheme by using a holographic optical tweezers setup equipped with a spatial light modulator that produces the LG beam as well as corrects the light wavefront. The light wavefront is modified adaptively to improve circular symmetry and uniformity of the orbit of a colloidal dielectric sphere revolving in mid-water under the irradiation of the LG beam.
Two-dimensional (2D) electron systems are promising for investigating correlated quantum phenomena. In particular, 2D oxides provide a platform that can host various quantum phases such as quantized Hall effect, superconductivity, or magnetism. The realization of such quantum phases in 2D oxides heavily relies on dedicated heterostructure growths.
