Multiplexing is a strategy to augment the transmission capacity of a communication system. It consists of combining multiple signals over the same data channel and it has been very successful in classical communications. However, the use of enhanced channels has only reached limited practicality in quantum communications (QC) as it requires the complex manipulation of quantum systems of higher dimensions. Considerable effort is being made towards QC using high-dimensional quantum systems encoded into the transverse momentum of single photons but, so far, no approach has been proven to be fully compatible with the existing telecommunication infrastructure. Here, we overcome such a technological challenge and demonstrate a stable and secure high-dimensional decoy-state quantum key distribution session over a 0.3 km long multicore optical fiber. The high-dimensional quantum states are defined in terms of the multiple core modes available for the photon transmission over the fiber, and the decoy-state analysis demonstrates that our technique enables a positive secret key generation rate up to 25 km of fiber propagation. Finally, we show how our results build up towards a high-dimensional quantum network composed of free-space and fiber based links.

This conceptual paper identifies future directions for information practices theoretical discourses addressing marginality, community, and embodiment. We extend arguments from critical research identifying how existing discourses fail to capture the nuanced, lived experiences of people and communities confronting marginalization, predominantly via their reinforcement of deficit narratives. We then connect a series of qualitative projects examining the information practices of lesbian, gay, bisexual, transgender, queer, intersex, and asexual communities in the American South with relevant Library and Information Science (LIS) research to examine how marginality, community, and embodiment shape these practices. Specifically, we introduce a conceptual model that describes marginality by framing information practices as tactical and agentic responses to and refutations of social and structural barriers and risks. While some of the information practices of participants and communities appear to be uninformed or unsafe, they represent the products of community sharing and vetting. Embodied navigations further inform participant practices as they navigate information worlds produced and informed by their intersectional identities. These arguments coincide with key categories established within our model that describe information practices: defensive and protective, and community and self. Based on these insights, we offer directions for future research and theory to reorient existing discourses in ways that inspire middle-range theory building that fully captures people's lived experiences.

We explore the propagation of the cylindrical vector beams (CVB) in turbid tissue-like scattering medium in comparison with the conventional Gaussian laser beam. The study of propagation of CVB and Gaussian laser beams in the medium is performed utilizing the unified electric field Monte Carlo model. The implemented Monte Carlo model is a part of a generalized on-line computational tool and utilizes parallel computing, executed on the NVIDIA Graphics Processing Units (GPUs) supporting Compute Unified Device Architecture (CUDA). Using extensive computational studies, we demonstrate that after propagation through the turbid tissue-like scattering medium, the degree of fringe contrast for CVB becomes at least twice higher in comparison to the conventional linearly polarized Gaussian beam. The results of simulations agree with the results of experimental studies. Both experimental and theoretical results suggest that there is a high potential of the application of CVB in the diagnosis of biological tissues.

No abstract

A correlated human red blood cell membrane fluctuation dependent on d-glucose concentration was found with dual time resolved membrane fluctuation spectroscopy (D-TRMFS). This new technique is a modified version of the dual optical tweezers method that has been adapted to measure the mechanical properties of red blood cells (RBCs) at distant membrane points simultaneously, enabling correlation analysis. Mechanical parameters under different d-glucose concentrations were obtained from direct membrane flickering measurements, complemented with membrane fluidity measurements using Laurdan Generalized Polarization (GP) Microscopy. Our results show an increase in the fluctuation amplitude of the lipid bilayer, and a decline in tension value, bending modulus and fluidity as d-glucose concentration increases. Metabolic mechanisms are proposed as explanations for the results.