Santipur College

Three sets of Cicer arietinum L. seeds were imbibed in magnetically treated water. Out of them two sets were exposed to magnetic fields – one set exposed to weak magnetic field and the other to strong magnetic field. Percentage of germination, speed of germination, emergence index, mean emergence time, vigour indices, shoot length, root length, fresh weight as well as dry weight of shoots and roots were studied. These three sets were compared with another set of seeds which were imbibed in non-magnetized water and not exposed to magnetic field. This set served as control. The best result in almost all parameters was observed in the set of seeds which were imbibed in magnetically treated water and kept under the constant influence of it but not exposed to magnetic fields. Seeds exposed to strong magnetic field drastically reduced the performance of the seeds in almost all parameters. From the present investigation it is evident that the most suitable measure for cultivation of chickpea under rain fed (unirrigated) conditions is the treatment of seeds with magnetized water before sowing because long roots have been found to be produced due to such treatment which would be suitable to absorb water from the deeper regions of soil, but for its cultivation in irrigated condition seeds should be treated with weak magnetic field for producing profuse lateral roots which would be more adaptive to such situations.

We present electromagnetically induced transparency (EIT) and double resonance optical pumping (DROP) spectra for the 5 S1/2-5 P3/2-5 D5/2 transitions of 87Rb atoms. Two-photon excitation to the 5 D5/2 state is confirmed by detecting 420 nm fluorescence from the decay channel 6 P3/2-5 S1/2. We observe a dual structure in the transmission profile for the closed transition (F =2-F' = 3-F '' = 4), which we attribute to competing DROP and EIT processes. A quantitative parameter K is introduced to characterize the DROP influence on EIT spectra. By adding a re-pumper field locked to the |5 S1/2, F = 1)-|5 P3/2, F' = 2) transition, we demonstrate clear EIT signal with suppressed DROP effects. Two-photon absorption is also observed in both probe transmission and blue fluorescence spectra. The steady state solution of the density matrix equations derived from our five-level analytical model is in good agreement with the experimental observations. Moreover, lock-in detection technique is used in the weak probe regime to achieve a high signal-to-noise ratio. These findings provide a deeper understanding of the mechanisms governing EIT and DROP in multi-level atomic systems and offer practical strategies for achieving DROP-free EIT signals, which are essential for cascade EIT-based applications like Rydberg spectroscopy, quantum information, and quantum memory. (c) 2026 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Thin films of chitosan and novel 2,6-pyridine-di-carboxylic acid (PCA) or dipicolinic acid (DPA) modified chitosan biopolymer composites were prepared using simple solvent casting method by incorporating three different doping concentrations of PCA into the chitosan matrix in a diluted aqueous solution to investigate the dielectric and conductive characteristics of the composites. The effect of incorporated PCA on the structure and properties of the composite were explored using X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy. The XRD profile demonstrated how the incorporation of PCA disrupt chitosan’s crystallinity and for 20 mass

This paper presents a study of the phase sensitivity of the transparency and absorption when a microwave (MW) field connects the two ground energy levels of a four-level N-type configuration. This four-level N-type system can be considered with the hyperfine energy levels of the D1 and/or D2 lines of 87Rb atoms. The effect of the MW field on electromagnetically induced transparency (EIT) and on absorption (EIA) is investigated in a weak pump region. Furthermore, we demonstrate that a small absorption dip appears on the top of the EIT in the strong probe region and the absorption dip gradually increases with the increasing value of the MW field at a specific off-detuning position of the pump laser field. The optical Bloch equations for the four-level N-type system are derived and the equations are solved numerically to obtain the results under steady state condition. Additionally, we show that by adjusting the phase of the MW field, a narrow EIT or EIA feature is converted into Autler–Townes Splitting (ATS) under the strong pump conditions.