### Browsing by Author "Salomaa, M. M."

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Item Comment on "Nucleation of He3-B from the a phase: A cosmic-ray effect?"(1985) Hakonen, P. J.; Krusius, M.; Salomaa, M. M.; Simola, J. T.; Department of Applied PhysicsItem Comment on 'Nucleation of 3He-B from the A Phase: A Cosmic-Ray Effect?'(American Physical Society (APS), 1985) Hakonen, Pertti J.; Krusius, M.; Salomaa, M. M.; Simola, J. T.; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceA comment to the article by Leggett, A. J.Item Continuous Vortices with Broken Symmetry in Rotating Superfluid 3He-A(American Physical Society (APS), 1984) Seppälä, H. K.; Hakonen, Pertti J.; Krusius, M.; Ohmi, T.; Salomaa, M. M.; Simola, J. T.; Volovik, G. E.; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceNew NMR measurements are reported on continuous 3He-A vortices in tilted magnetic fields. We introduce a symmetry classification of the continuous vortices with broken axial symmetry. It is found that the discrete internal symmetry may in addition be broken in two inequivalent ways, producing two different continuous vortices. Although NMR may not distinguish between these two vortices, the observed vortex satellite peak is well accounted for by spin waves localized in the soft core of such vortices.Item Internal Magnus effects in superfluid 3A(American Physical Society (APS), 1989) Salmelin, Riitta; Salomaa, M. M.; Mineev, V. P.; Neurotieteen ja lääketieteellisen tekniikan laitos; Department of Neuroscience and Biomedical Engineering; Perustieteiden korkeakoulu; School of ScienceOrbital angular momentum of the coherently aligned Cooper pairs in superfluid 3A is encountered by an object immersed in the condensate. We evaluate the associated quasiparticle-scattering asymmetry experienced by a negative ion; this leads to a measureable, purely quantum-mechanical reactive force deflecting the ion’s trajectory. Possible hydrodynamic Magnus effects are also discussed.Item Internal magnus effects in superfluid 3He-A(1989-08) Salmelin, R. H.; Salomaa, M. M.; Mineev, V. P.; Department of Applied PhysicsOrbital angular momentum of the coherently aligned Cooper pairs in superfluid A3 is encountered by an object immersed in the condensate. We evaluate the associated quasiparticle-scattering asymmetry experienced by a negative ion; this leads to a measureable, purely quantum-mechanical reactive force deflecting the ions trajectory. Possible hydrodynamic Magnus effects are also discussed.Item Magnetic Vortices in Rotating Superfluid 3He-B(1983-10) Hakonen, P. J.; Krusius, M.; Salomaa, M. M.; Simola, J. T.; Bunkov, Yu. M.; Mineev, V. P.; Volovik, G. E.; Department of Applied PhysicsRotating superfluid He3-B is found to possess a new contribution to the NMR frequency shift, which changes sign on reversal of either the angular velocity of rotation or the magnetic field. For p=29.3 bars this gyromagnetic effect shows a discontinuity in magnitude at the first-order phase-transition temperature TTc=0.6, at which a change in the vortex-core structure takes place. These observations support the conclusion that the vortex core possesses a spontaneous intrinsic magnetization.Item Magnetic Vortices in Rotating Superfluid 3He-B(American Physical Society (APS), 1983) Hakonen, Pertti J.; Krusius, M.; Salomaa, M. M.; Simola, J. T.; Bunkov, Yu. M.; Mineev, V. P.; Volovik, G. E.; Teknillisen fysiikan laitos; Department of Applied Physics; Perustieteiden korkeakoulu; School of ScienceRotating superfluid 3He-B is found to possess a new contribution to the NMR frequency shift, which changes sign on reversal of either the angular velocity of rotation or the magnetic field. For p=29.3 bars this gyromagnetic effect shows a discontinuity in magnitude at the first-order phase-transition temperature T/Tc=0.6, at which a change in the vortex-core structure takes place. These observations support the conclusion that the vortex core possesses a spontaneous intrinsic magnetization.Item Resonant quasiparticle-ion scattering in anisotropic superfluid 3He(American Physical Society (APS), 1990) Salmelin, Riitta; Salomaa, M. M.; Neurotieteen ja lääketieteellisen tekniikan laitos; Department of Neuroscience and Biomedical Engineering; Perustieteiden korkeakoulu; School of ScienceLow-energy excitations in quantum fluids are most directly encountered by ions. In the superfluid phases of 3He the relevant elementary excitations are Bogoliubov quasiparticles, which undergo repeated scattering off an ion in the presence of a divergent density of states. We present a quantum-mechanical calculation of the resonant 3He quasiparticle-scattering-limited mobility for negative ions in the anisotropic bulk 3A (A phase) and 3P (polar phase) that is exact when the quasiparticles scatter elastically. We develop a numerical scheme to solve the singular equations for quasiparticle-ion scattering in the A and P phases. Both of these superfluid phases feature a uniaxially symmetric order parameter but distinct topology for the magnitude of the energy gap on the Fermi sphere, i.e., points versus lines of nodes. In particular, the perpetual orbital circulation of Cooper pairs in 3A results in a novel, purely quantum-mechanical intrinsic Magnus effect, which is absent in the polar phase, where Cooper pairs possess no spontaneous orbital angular momentum. This is of interest also for transport properties of heavy-fermion superconductors. We discuss the 3He quasiparticle-ion cross sections, which allow one to account for the mobility data with essentially no free parameters. The calculated mobility thus facilitates an introduction of ‘‘ion spectroscopy’’ to extract useful information on fundamental properties of the superfluid state, such as the temperature dependence of the energy gap in 3A.Item Resonant quasiparticle-ion scattering in anisotropic superfluid 3He(1990-03) Salmelin, R. H.; Salomaa, M. M.; Department of Applied PhysicsLow-energy excitations in quantum fluids are most directly encountered by ions. In the superfluid phases of He3 the relevant elementary excitations are Bogoliubov quasiparticles, which undergo repeated scattering off an ion in the presence of a divergent density of states. We present a quantum-mechanical calculation of the resonant He3 quasiparticle-scattering-limited mobility for negative ions in the anisotropic bulk A3 (A phase) and P3 (polar phase) that is exact when the quasiparticles scatter elastically. We develop a numerical scheme to solve the singular equations for quasiparticle-ion scattering in the A and P phases. Both of these superfluid phases feature a uniaxially symmetric order parameter but distinct topology for the magnitude of the energy gap on the Fermi sphere, i.e., points versus lines of nodes. In particular, the perpetual orbital circulation of Cooper pairs in A3 results in a novel, purely quantum mechanical intrinsic Magnus effect, which is absent in the polar phase, where Cooper pairs possess no spontaneous orbital angular momentum. This is of interest also for transport properties of heavy-fermion superconductors. We discuss the He3 quasiparticle-ion cross sections, which allow one to account for the mobility data with essentially no free parameters. The calculated mobility thus facilitates an introduction of ion spectroscopy to extract useful information on fundamental properties of the superfluid state, such as the temperature dependence of the energy gap in A3.