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We present a formula for tunneling conductance in ballistic ferromagnet/ferromagnetic insulator/superconductor junctions where the superconducting state has opposite spin pairing symmetry. The formula can involve correctly a ferromagnetism has been induced by effective mass difference between up- and down-spin electrons. Then, this effective mass mismatch ferromagnet and standard Stoner ferromagnet have been employed in this paper. As an application of the formulation, we have studied the tunneling effect for junctions including spin-triplet p-wave superconductor. The conductace spectra show a clear difference between two ferromagnets depending upon the way of normalization of the conductance. Especially, a essential difference is seen in zero-bias conductance peaks reflecting characteristics of each ferromagnets. From obtained results, it will be suggested that the measurements of the tunneling conductance in the junction provide us a useful information about the mechanism of itinerant ferromagnetism in metal., Comment: 8 pages, 8 figures, references added to the first version

To clarify the origin of anomalous behaviors in Pb/Sr2RuO4/Pb junctions in terms of the pairing symmetry, a theory of the d.c. Josephson current in s-wave superconductor / p-wave superconductor / s-wave superconductor junctions is developed. Calculated results on the temperature dependence of the critical Josephson current exhibit non-monotonous behaviors when the thickness of the p-wave superconductor is comparable to the coherence length. The consistency between present results with recent experimental measurement supports the possibility of a unitary p-wave pairing state in Sr2RuO4., Comment: 6 pages, 4 eps figures

The properties of Josephson junction including a ferromagnetic insulating layer are studied theoretically. The calculated current shows the anomalous dependence on the magnitude of the exchange interaction at the interface. The Josephson junction changes from 0-junction to $\pi$-junction with the increase of the magnitude of the exchange interaction., Comment: 3 pages Latex, 4 eps figures

A theory of tunneling conductance spectra for normal metal/insulator/Sr$_{2}$RuO$_{4}$ junction is studied theoretically. We assume several types of pair potentials with triplet symmetries that are promising candidates for Sr$_{2}$RuO$_{4}$. The calculated conductance spectra show either zero bias peaks or gap like structures depending on the orientations of the junctions. The existence of a residual components in the gap reflects a non-unitary property of the superconducting states. Based on the calculation of a temperature dependence, we will verify that the measurement temperature below 100mK is required to determine the pairing symmetry experimentally., Comment: 3pages, 4 PostScript figures. revised about an error on the format

Tunneling conductance spectra of normal metal/insulator/triplet superconductor junctions are investigated theoretically. As triplet paring states we select several types of symmetries that are promising candidates for the superconducting states in UPt$_{3}$ and in Sr$_{2}$RuO$_{4}$. The calculated conductance spectra are sensitive to the orientation of the junction which reflects the anisotropy of the pairing states. They show either zero-bias conductance peaks or gap-like structures depending on the orientation of the junctions. The existence of a residual density of states, peculiar to nonunitary states, is shown to have a significant influence on the properties of the conductance spectra. Present results serve as a guidefor the experimental determination of the symmetry of the pair potentials in UPt$_{3}$ and Sr$_{2}$RuO$_{4}$., Comment: 10 pages, 11 eps figures, J.Phys.Soc.Jpn.67,No.9(1998)