Magnetic skyrmions, a topologically stable spin swirling object, have attracted a great interest due to their potential applications in future spintronics and ultra high dense magnetic memory devices. Cu 2 OSeO 3 is only known insulating chiral helimagnet with multiple phases including skyrmion phase. Existence of skyrmion phase as well as first and second order phase transitions make Cu 2 OSeO 3 a promissing candidate for investigating complex magnetic phenomena. Here, we report that both first and second order magnetic phase transitions are responsible in determining the phase diagram with atleast two multicritical point in Cu 2 OSeO 3 . Fluctuation-induced first order transition is realized as a precursor for skyrmion phase over a small window of temperature of magnetic field. The evolution of field dependent entropy at the phase transition provides the evidence for tricritical point. Furthermore, existence of commensurate and incommensurate phases, alongwith co-existence of three second order phase transitions provide evidence for the existence of Lifshitz point.1 arXiv:1907.13574v1 [cond-mat.str-el]

Under new “make in India policy” India has started to become global manufacturing hub and many Indian organizations are looking to implement lean philosophy to gain sustainable strategic benefits over others. Therefore, a need was felt to develop comprehensive lean evaluation system for Indian automotive small & medium sized enterprises in order to measure its present lean status and potential improvements to gain significant strategic advantages. Research started with the identification of various lean factors and associated sub factors through literature survey. Fuzzy analytic hierarchy process was applied to assign weight to various extracted lean factors and sub factors because of its evident merits. Fuzzy comprehensive analysis was applied to assess present status of Indian automotive small and medium sized enterprises, where lean does not practice. Lean performance of Indian automotive small & medium sized enterprises was ascertained as poor. The proposed model could be useful to guiding the Indian automotive small and medium sized enterprises in judicial selection of lean practices to gain significant sustainable strategic advantage over its competitors. Novelty of this research is to emerge from the development of comprehensive lean measurement model for Indian small and medium sized enterprises in automotive sector.

Here, we report three magnetic transitions at 101 K (T$$_{C1}$$ C 1 ), 246 K (T$$_{C2}$$ C 2 ) and 295 K (T$$_{C3}$$ C 3 ) in bilayer La$$_{1.4}$$ 1.4 Sr$$_{1.6}$$ 1.6 Mn$$_{2}$$ 2 O$$_7$$ 7 . The second order phase transitions have been identified at these transition points with the help of change in entropy analysis and modified Arrott plots (MAPs). The critical behavior around T$$_{C1}$$ C 1 , T$$_{C2}$$ C 2 and T$$_{C3}$$ C 3 have been studied by MAPs and Kouvel–Fisher method. Based on these analyses four magnetic phases are: (1) 2D Ising ferromagnetic (FM) below T$$_{C1}$$ C 1 ,(2) 2D Heisenberg canted antiferromagnetic (CAFM-I) and FM clusters in temperature range T$$_{C1}$$ C 1 < T < T$$_{C2}$$ C 2 , (3) 2D Heisenberg CAFM-II and FM clusters with non magnetically interacting planes in temperature range T$$_{C2}$$ C 2 < T < T$$_{C3}$$ C 3 and (4) paramagnetic for T > T$$_{C3}$$ C 3 .

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