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If neutrinos get mass via the seesaw mechanism the mixing matrix describing neutrino oscillations can be effectively nonunitary. We show that in this case the neutrino appearance probabilities involve a new CP phase associated with nonunitarity. This leads to an ambiguity in extracting the "standard" three-neutrino phase δCP, which can survive even after neutrino and antineutrino channels are combined. Its existence should be taken into account in the planning of any oscillation experiment aiming at a robust measurement of δCP. [ABSTRACT FROM AUTHOR]

The interdependences of different phase transitions in Mott materials are fundamental to the understanding of the mechanisms behind them. One of the most important relations is between the ubiquitous structural and electronic transitions. Using IR spectroscopy, optical reflectivity, and x-ray diffraction, we show that the metal-insulator transition is coupled to the structural phase transition in V_{2}O_{3} films. This coupling persists even in films with widely varying transition temperatures and strains. Our findings are in contrast to recent experimental findings and theoretical predictions. Using V_{2}O_{3} as a model system, we discuss the pitfalls in measurements of the electronic and structural states of Mott materials in general, calling for a critical examination of previous work in this field. Our findings also have important implications for the performance of Mott materials in next-generation neuromorphic computing technology.

Successful leptogenesis within the simplest type I supersymmetric seesaw mechanism requires the lightest of the three right-handed neutrino supermultiplets to be heavier than approximately 10(9) GeV. Thermal production of such (s)neutrinos requires very high reheating temperatures which result in an overproduction of gravitinos with catastrophic consequences for the evolution of the Universe. In this Letter, we let R parity be violated through a lambda(i)N(i)H(u)H(d) term in the superpotential, where N(i) are right-handed neutrino supermultiplets. We show that in the presence of this term, the produced lepton-antilepton asymmetry can be enhanced. As a result, even for N1 masses as low as 10(6) GeV or less, we can obtain the observed baryon asymmetry of the Universe without gravitino overproduction.