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Krishna Begari

Publications and source records attributed to Krishna Begari.

2 recordsLinked to original sources

Static-Dynamic Correlations and Complex Spin-Wave Eigenmodes in Single- and Multilayer Diamond-Shaped Nanomagnets Without Bias Field

Diamond-shaped nanomagnets provide a suitable platform for developing microwave devices with reconfigurable characteristics. In this study, the static and dynamic magnetic behaviour of single layer and multilayer diamond-shaped nanomagnets was systematically investigated using micromagnetic simulations. Two distinct remanent magnetic configurations were obtained through a simple magnetic field initialization process. These configurations exhibited different magnetization patterns and dynamic responses. Their resonance characteristics could be modified by applying a nanosecond-scale magnetic field pulse, enabling reconfigurable microwave operation. A clear resonance frequency shift in the sub-GHz (0.9 GHz) range was observed for the single-layer structure, while the multilayer structure exhibited a significantly larger frequency shift in the GHz range (3 GHz). The larger frequency tunability observed in the multilayer configuration arises primarily from the enhanced dipolar coupling between the vertically coupled magnetic layers, which modifies the local effective magnetic field and consequently influences the magnetization dynamics. These findings demonstrate that diamond-shaped nanomagnets can provide a simple and effective route toward reconfigurable microwave functionality, with potential applications in ultralow-power, ultrafast, and frequency tunable microwave devices.

cond-mat.mes-hall

Micromagnetic Design of Bias-Free Reconfigurable Microwave Properties in Hexagonal Shaped Multilayer Nanomagnets

Magnetic miniaturized nanostructures hold great promise for current and future microwave technologies due to their magnetization dynamics in the GHz frequency range. This work presents a method for investigating reconfigurable microwave properties using a novel hexagonal nanomagnet structure. Micromagnetic simulations are employed to investigate the magnetic static and dynamic properties of the nanomagnets. A simple field initialization method is used to examine two distinct magnetic remanent states in each sample. A nanosecond-width magnetic pulse field can be applied to tune the unique magnetization dynamics parameters corresponding to the different remanent states. Find that for both single-layer and multilayer nanomagnets, there is a notable frequency shift in the sub-GHz and GHz regions between the two distinct magnetic remanent states.

cond-mat.mes-hall