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The investigation of integrated frequency comb sources characterized by equidistant spectral modes was initially driven by considerations towards classical applications, seeking a more practical and miniaturized way to generate stable broadband sources of light. Recently, in the context of scaling the complexity of optical quantum circuits, these on-chip approaches have provided a new framework to address the challenges associated with non-classical state generation and manipulation. For example, multi-photon and high-dimensional states were to date either inaccessible, lacked scalability, or were difficult to manipulate, requiring elaborate approaches. The emerging field of quantum frequency combs studying spectral multimode Manuscript

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An investigation was carried out to find out the occurrence and abundance of copepods in relation to physico-chemical parameters in a fish pond within the Rajshahi University Campus, Rajshahi, Bangladesh from December, 2006 to September, 2007. A total of 5 genera of copepods of which 2 species belong to Cyclops were identified. Highest density of copepods (768 units/l) was observed in May 2007. Seasonal succession of copepods showed the most abundance in spring, followed by winter, summer and autumn. Correlationship between different physico-chemical parameters and copepods were also analyzed.

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This investigation deals with the mortality rate of fish seeds (Labeo rohita) during traditional transportation system; to evaluate the effects of loading density with time scale under different water medium; temperature effect with relation to fry size and oxygen consumption; and the effect of saline water bath before transportation. Mortality rates were significantly increased with time scale and loading density under different water medium. Higher mortality was observed at 400 g L -1 loading density (river water 82%, pond water 70% and tubewell water 67.5%) than at 200 g L -1 and 300 g L -1 loading density after 24h. Oxygen consumption rate increased significantly with increasing temperature and decreased significantly with increasing fry body weight. Therefore, mortality rate could decrease (22%) if fish fry are bathed in saline water before journey and tubewell water can be use as a medium for long distance transportation.

Well-controlled yet practical systems that give access to interference effects are critical for established and new functionalities in ultrafast signal processing, quantum photonics, optical coherence characterization, etc. Optical fiber systems constitute a central platform for such technologies. However, harnessing optical interference in a versatile and stable manner remains technologically costly and challenging. Here, degrees of freedom native to optical fibers, i.e., polarization and frequency, are used to demonstrate an easily deployable technique for the retrieval and stabilization of the relative phase in fiber interferometric systems. The scheme gives access (without intricate device isolation) to <1.3 × 10 −3 rad error signal Allan deviation across 1 ms to 1.2 h integration times for all tested phases, ranging from 0 to 2 . More importantly, the phase-independence of this stability is shown across the full 2 range, granting access to arbitrary phase settings, central for, e.g., performing quantum projection measurements and coherent pulse recombination. Furthermore, the scheme is characterized with attenuated optical reference signals and single-photon detectors, and extended functionality is demonstrated through the use of pulsed reference signals (allowing time-multiplexing of both main and reference signals). Finally, the scheme is used to demonstrate radiofrequency-controlled interference of high-dimensional time-bin entangled states.