QFS2016 Book of Abstracts

Abstracts

P2.33 The spectroscopy of collective modes in unconventional superconductors and superfluids Brusov Peter(1), Filatova Tatiana(2) (1) Financial University, Applied Mathematics faculty, Moscow (2) Financial University, Financial manegement faculty, Moscow 49 Leningradsky Prospekt, Moscow, Russia, 125993, GSP-3 We study the collective properties of unconventional superconductors and superfluids. We consider superfluid phases of 3 He within path integral technique and calculated the complete collective mode spectrum in different phases of superfluid 3 He. After the discovery of collective modes in unconventional superconductors (USC), their study becomes very important. Collective modes (CM) in HTSC exhibit themselves in many experiments: ultrasound attenuation (UA) and microwave absorption (MWA), neutron scattering, photoemission and Raman scattering, etc. The contribution of collective modes to UA and MWA may be substantial. We consider two-dimensional and three-dimensional models of p- and d-pairing for superconductors built by the path integration technique. Within these models we calculate the collective excitations in different unconventional superconductors [high temperature superconductors (HTSC), heavy fermion superconductors (HFSC), etc.] under p- and d-pairing. We consider both bulk and 2D systems. Some recent ideas concerning realization in HTSC of the mixtures of different states are investigated. Obtained results could be used for interpretation of the sound attenuation and microwave absorption data as well as for identifcation of the type of pairing and order parameter in unconventional superconductors. They allow us to distinguish pure d-wave state from the mixture of two d-wave states in HTSC. We create new direction in unconventional superconductors and superfluids: “The spectroscopy of collective modes”. P2.34 Superfluid 3 He-B in the vicinity of a boundary Brusov Peter(1), Filatova Tatiana(2) (1) Financial University, Applied Mathematics faculty, Moscow (2)Financial University, Financial management faculty, Moscow 49 Leningradsky Prospekt, Moscow, Russia, 125993, GSP-3. We have analyzed transverse sound experiments in superfluid 3 He -B, where some peaks in the transverse sound absorption have been observed. Our analysis of existing experimental data leads us to a conclusion that the deformed B phase is realized near the boundary. This implies that the influence of the wall or, speaking in general, of any confined geometry does not lead to the existence of a new phase near the boundary, but the wall deforms the order parameter of the B phase and this deformation leads to some important consequences.

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