Phys.org July 2, 2024
To achieve global quantum internet preparing and manipulating N-dimensional flying qudits as well as subsequently establishing their entanglement are still challenging tasks. A team of researchers in the US (University of Pennsylvania, Duke University, College of Staten Island) used an integrated approach, to explore the synergy from two degrees of freedom of light, spatial mode and polarization, to generate, encode, and manipulate flying structured photons and their formed qudits in a four-dimensional Hilbert space with high quantum fidelity, intrinsically enabling enhanced noise resilience and higher quantum data rates. The four eigen spin–orbit modes of their qudits possessed identical spatial–temporal characteristics in terms of intensity distribution and group velocity, thereby preserving long-haul coherence within the entirety of the quantum data transmission link. Leveraging the bi-photon entanglement they presented versatile spin–orbit cluster states in an extensive dimensional Hilbert space. According to the researchers such cluster states hold the promise for quantum error correction which can further bolster the channel robustness in long-range quantum communication… read more. Open Access TECHNICAL ARTICLEÂ
Schematic for generation and manipulation of spin–orbit flying qudits… Credit: eLight volume 4, Article number: 10 (2024)