Vortices in superconductors By Charles Simon Laboratoire national

“Vortices in superconductors" By Charles Simon Laboratoire national des champs magnétiques intenses, Grenoble

Thanks to : A. Pautrat, C. Goupil from CRISMAT Caen A. Brulet, C. Dewhurst from LLB and ILL P. Mathieu, B. Placais, Y. Simon from ENS Paris and A. Ruyter from LEMA Tours

« NRS » in H 2 S Science 351, 1303 (2016)

« NRS » in H 2 S The nuclear levels of Sn 119 are split by the magnetic field and create oscillations versus time

« NRS » in future Nuclear Resonance Scattering This technique seems to be very powerful to measure magnetic field in very small areas (200 x 200 nm 2). Question : what can be studied by this technique ?

Existing techniques Transmission Electronic Microscopy Vortex decoration Hall probes Magneto-optics ms. R Tunnel microscope Neutron Scattering

Critical currents in superconductors Vortex lattice Pinning displacement

Lorentz Microscopy (TEM) ] K. Harada, T. Matsuda, J. E. Bonevich, M. Igarashi, S. Kondo, G. Pozzi, U. Kawabe and A. Tonomura, Nature 360 (1992) 51.

Vortex decoration (optics) 9

Optical magneto optics M. V. Indenbaum et al. , Phys Rev. Lett. 84, 1792 (2000) 10

Hall probe array E. Altshuler, Phys. Rev. B 70, 140505 (2004). 11

ms. R technique : 135. 5 MHz T− 1 12

Scanning tunnel microscope Nb. Se 2 13

Scanning tunnel microscope Nb. Se 2 14

Neutron diffraction on a small angle spectrometer l = 15 A a =1500 A H = 900 G

Rocking curves in Pb-In 10% Curl B = m 0 J

Neutron spin echo measurement : verification of the Josephson relation

Effect of the surface treatment on Pb-In crystals

Mathieu Simon Model

Role of the anisotropy in a flat sample : surface roughness

An exemple : Nb. Se 2

Bi 2 Sr 2 Ca. Cu 2 O 24

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A. Pautrat, et al. , Phys. Rev. B 90, 087002 (2003) 27

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Conclusion : A new technique like NRS with this spatial resolution (200 nm) may be useful to adress unresolved problems in vortex in superconductors A special setup to control magnetic field on the sample is needed.