Abstract
Quantum key distribution – a process that encodes digital information – often utilises fibre optic technologies for commercial applications. Fibre provides the benefit of a dark channel as well as the convenience of independence of a line-of-sight connection between the sender and receiver. In order to implement quantum key distribution protocols utilising polarisation encoding, the birefringence effects of fibre must be compensated for. Birefringence is caused by manufacturing impurities in the fibre or a change in environmental conditions and results in a rotation of the state of polarisation of light as it is propagated through the fibre. With dynamic environmental conditions, the birefringence effects should be monitored with a test signal at regular time intervals so that the polarisation of each photon can be appropriately compensated to its original state. Orthogonal states are compensated simultaneously, but most protocols, such as BB84 and B92, require non-orthogonal basis sets. Instead of using a compensator for each basis, the presented scheme fixes the polarisation controller onto the plane on the Poincaré that passes through both bases, compensating both non-orthogonal bases simultaneously.
Highlights
Journals are the main vehicle for scholarly communication within the academic community
We identify whether the newly added South African journals in the Journal Citation Reports® (JCR) are of similar quality as the pre-existing journals
The impact factor of a journal is defined as the quotient between the number of times an article published in the journal in the previous 2 years is cited in the year of observation and the number of articles this journal has published in these previous 2 years
Summary
Journals are the main vehicle for scholarly communication within the academic community. Assessments of journals are of interest to a number of stakeholders from scientists and librarians to research administrators, editors, policy analysts and policymakers and for a variety of reasons. Researchers would like to know where to publish in order to maximise the exposure of their research, and what to read in order to keep abreast of developments in their fields within the time constraints they face. Librarians would like to keep available the most reputed journals within their budget constraints. Research administrators use journal assessments in their evaluations of academics for recruitment, promotion and funding reasons.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
