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Recently, there has been substantial interest in realizations of skyrmions, in particular in quasi-2D systems due to increased stability resulting from reduced dimensionality. A stable skyrmion, representing the smallest realizable magnetic texture, could be an ideal element for ultra-dense magnetic memories. Here, we use the most general form of the quasi-2D free energy with DzyaloshinskiiMoriya interactions constructed from general symmetry considerations reflecting the underlying system. We predict that skyrmion phase is robust and it is present even when the system lacks the in-plane rotational symmetry. In fact, the lowered symmetry leads to increased stability of vortex-antivortex lattices with four-fold symmetry and in-plane spirals, in some instances even in the absence of an external magnetic field. Our results relate different hexagonal and square cell phases to the symmetries of materials used for realizations of skyrmions. This will give clear directions for experimental realizations of hexagonal and square cell phases, and will allow engineering of skyrmions with unusual properties. We also predict striking differences in gyro-dynamics induced by spin currents for isolated skyrmions and for crystals where spin currents can be induced by charge carriers or by thermal magnons. We find that under certain conditions, isolated skyrmions can move along the current without a side motion which can have implications for realizations of magnetic memories.

Nepal has been suffering from a serious energy crisis for decades. It has severely affected its economic, social and political developments. Owing to the continuously evolving energy situation in Nepal, and the recent progress in renewable energy technologies, this study aims to provide an up to date perspective on the current energy crisis in Nepal. In particular, the current energy production and consumption profiles are reviewed, and the main factors contributing to a widening gap between the energy supply and demand are identified. These factors concern delayed and overpriced hydropower projects, outdated and insufficient energy infrastructure, transmission and distribution losses, energy theft, deficient energy management, lack of energy conservation, low efficiency of equipment, unsustainable energy pricing strategies and unsatisfying energy market regulations. Other essential factors worsening the energy crisis can be attributed to specific geographical and geopolitical problems, the strong dependence on energy imports, and inadequate exploitation of the vast amounts of renewable energy resources. The status of existing and planned large hydropower projects is summarized. The recent policies and investment initiatives of the Nepalese government to support green and sustainable energy are discussed. Furthermore, a long-term outlook on the energy situation in Nepal is outlined using the energy modeling software LEAP in order to show how to exploit the tremendous renewable energy resources in Nepal. Our findings suggest that renewable resources are crucial not only for mitigating the present energy crisis, but also to ultimately provide energy independence for Nepal by establishing reliable and secure sources of energy.

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