5 papers
Quantum Gouy phase singularities in a propagating biphoton state
Takumi Jinushi, Hirokazu Kobayashi
Phase singularities are topological defects around which the phase winds by an integer multiple of . In entangled multiphoton states, they can emerge nonlocally in the joint wa…
Comparative analysis of wavenumber response in phase contrast and spiral phase imaging systems for plasma diagnostics
Jigme Zangpo, Hirokazu Kobayashi, Haruki Kawaguchi +1
Phase contrast imaging (PCI) has been used for decades to study plasma density fluctuations, but its wavenumber response is constrained by the phase plate groove width and beam…
Phase-edge imaging using q-plate shifts for faster and simpler microscopy
Jigme Zangpo, Hirokazu Kobayashi, Ryo Yasuhara
We present a simplified method for isolating the edges of a phase object from the edges of an amplitude object using a 4f system with an off-axis q-plate. Instead of the four off-a…
Single-pixel edge enhancement of object via convolutional filtering with localized vortex phase
Jigme Zangpo, Hirokazu Kobayashi
Microscopy is an essential tool in imaging research, and the edge-enhanced microscope by using the vortex filter is of particular interest as an optical information processing that…
Optical response of edge modes in time-reversal symmetric topological superconductors
Hirokazu Kobayashi, Han Bi, James Jun He +1
Topological superconductors and Majorana edge modes at their boundaries have been theoretically predicted. However, their experimental observation remains controversial. Recent the…