### Super-resolved angular displacement estimation based upon a Sagnac interferometer and parity measurement

Author(s):

Jian-Dong Zhang, Zi-Jing Zhang, Long-Zhu Cen, Jun-Yan Hu and Yuan Zhao

Abstract:

“Super-resolved angular displacement estimation is of crucial significance to the field
of quantum information processing. Here we report an estimation protocol based on a Sagnac
interferometer fed by a coherent state carrying orbital angular momentum. In a lossless scenario,
through the use of parity measurement, our protocol can achieve a 4-fold super-resolved output
with quantum number ; meanwhile, a shot-noise-limited sensitivity saturating the quantum
Cramér-Rao bound is reachable. We also consider the effects of several realistic factors, including
nonideal state preparation, photon loss, and inefficient measurement. Finally, with mean photon
number 𝑁¯ = 2.297 and ℓ = 1 taken, we experimentally demonstrate a super-resolved effect of
angular displacement with a factor of 7.88.”

Publication: Optics Express
Issue/Year: Vol. 28, Issue 3, pp. 4320-4332
DOI: 10.1364/OE.384082

### Three-Dimensional Holographic Reconstruction of Brain Tissue Based on Convolution Propagation

Author(s):

Rania M. Abdelazeem and Doaa Youssef and Jala El-Azab and Salah Hassab-Elnaby and Mostafa Agour

Abstract:

” In this study, a dynamic holographic projection system for brain tissue and its anatomical structures extracted from Magnetic Resonance (MR) plane slice is reported. Computer holograms are calculated using a modied Gerchberg-Saxton (GS) iterative algorithm where the projection is based on the plane wave decomposition. First, brain anatomy includes white matter (WM), grey matter (GM) and brain tissue are extracted. Then, phase holograms using the proposed method are generated. Finally, single phase hologram for the whole brain anatomy is generated and is optically reconstructed by a phase-only spatial light modulator (SLM) at dierent depths. The obtained results revealed that the three-dimensional holographic projection of MR brain tissue can aid to provide better interpretation of brain anatomical
structure to achieve better diagnostic results.”

Publication: Journal of Physics: Conference Series
Issue/Year: Vol. 1472
DOI: 10.1088/1742-6596/1472/1/012008

### Microchannels inside bulk PMMA generated by femtosecond laser using adaptive beam shaping

Author(s):

Roth, Gian-Luca; Rung, Stefan; Esen, Cemal & Hellmann, Ralf

Abstract:

“In this contribution, we report on the generation of internal microchannels with basically unlimited channel length inside of PMMA bulk material by femtosecond laser. A precisely controllable and stable circular channel cross section is obtained by using a spatial light modulator to compensate the writing depth depending spherical aberration. Furthermore, the generation of a rotatable elliptical input beam by adaptive optics ensures a fitting of the beam shaping to the writing direction. In this study, we report on both, the effect of the ellipticity of the input beam and the effect of a correction of the spherical aberration on the circularity of the resulting internal microchannels. Moreover, we demonstrate the application of this writing technique by creating microfluidic testing structures inside of a transparent standard polymer.”