BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:A.V. Sergienko DTSTART:20240911T134000Z DTEND:20240911T151000Z DTSTAMP:20260423T005715Z UID:QOART/55 DESCRIPTION:Title: D irectionally unbiased linear optics enable novel high-resolution sensors a nd quantum network routers\nby A.V. Sergienko as part of Quantum Optic s and Related Topics\n\n\nAbstract\nGrover multiports are higher-dimension al generalizations of beam splitters in which inputs to any of the four po rts have an equal probability of exiting at any of the four ports\, includ ing the input port. This offers direct access to a greater number of degre es of freedom [1]: We demonstrate that traditional interferometers can obt ain novel features when directionally unbiased multi-ports replace traditi onal beam splitters. It will be shown that the Grover-based counterpart of the conventional Michelson interferometer can substantially enhance the p hase measurement resolution.\nThe Grover-Michelson interferometer demonstr ates a tunable intensity-phase slope instead of a traditional fixed cos2 p rofile\, thus enabling super-resolution phase measurement while utilizing only linear optical elements and classical states of light [2].\nThe tradi tional two-photon Hong-Ou-Mandel (HOM) effect could be expanded onto a hig herdimensional set of four spatial modes when combining the Grover coin wi th quantum-correlated twophoton input and coincidence measurements. We int roduce a novel quantum photonic state router design that allows controllab le redistribution (switching) of (|2\,0>+|0\,2>) quantum states over these four modes using directionally unbiased linear-optical four-ports without post-selection [3]. The original HOM effect only enables photon pairs to exit in two directions in space. However\, when beam splitters and phase s hifters accompany the Grover coin\, the result is a directionally controll able two-photon HOM effect in four spatial modes\, with the outgoing photo n direction controlled by changing the phases in the system. By this means \, spatial and temporal control of the propagation of the two-photon super position state through a network or quantum nodes (quantum state routing) can be achieved.\n\n[1] Shuto Osawa\, David S. Simon\, and Alexander V. Se rgienko "Directionally-Unbiased Unitary Optical Devices in Discrete-Time Q uantum Walks\,” Entropy\, v. 21\, p. 853 (2019).\n\n[2] Christopher R. S chwarze\, David S. Simon\, and Alexander V. Sergienko\,'' Enhanced-Sensiti vity Interferometry With Phase-Sensitive Unbiased Multiports\,” Phys. Re v. A 107\, 052615 (2023)\n\n[3] Shuto Osawa\, David S. Simon\, and Alexand er V. Sergienko "Higher-Dimensional Hong-Ou-Mandel Effect and State Redist ribution With Linear-Optical Multiports\,” Phys. Rev. A 102\, 063712 (20 20).\n LOCATION:https://researchseminars.org/talk/QOART/55/ END:VEVENT END:VCALENDAR