MASc Seminar: Quantum experiments with single-photon spin-orbit lattice arrays

Friday, September 6, 2019 10:00 am - 10:00 am EDT (GMT -04:00)

Candidate: Ruoxuan Xu

Title: Quantum experiments with single-photon spin-orbit lattice arrays

Date: September 6, 2019

Time: 10:00am

Place: EIT 3145

Supervisor(s): Bajcsy, Michal - Resch, Kevin (Quantum Computing)

Abstract:

I will introduce two single-photon experiments with the lattice of spin-orbit arrays.

In the first work, we implement a remote state preparation protocol on our single-photon OAM lattice state via hybrid-entanglement. Remote state preparation is a variant of quantum state teleportation where the sender knows the transmitted state. It is known to require fewer classical resources and exhibits a nontrivial tradeoff between the entanglement and classical communication compared with quantum teleportation. Here we propose a state preparation scheme between two spatially separated photons sharing a hybrid-entangled polarization-orbital angular momentum state. By sending one of the polarization-entangled photon pairs through Lattice of Optical Vortex prism pairs, we generate a two-dimensional lattice of spin-orbit coupled single-photons. We show that the measurement taken by an intensified CCD camera on the transformed photons can be remotely manipulated by the polarization projection of the other. Our protocol could have a significant impact on long-distance quantum communication with higher channel capacity and lead to more efficient and compatible quantum information processing techniques.

The second experiment investigates the single-photon Talbot Effect in spin-orbit arrays. Talbot Effect is a near-field diffraction effect, that occurs with the propagation of periodically structured waves. It has enabled several unique applications in optical metrology, image processing, data transmission, and matter-wave interferometry. We observe that upon propagation, the wavefronts of the single photons manifest self-imaging whereby the OAM lattice intensity profile is recovered. Furthermore, we show that the intensity at fractional Talbot distances is indicative of a periodic helical phase structure corresponding to a lattice of OAM states.