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O-28 37 Spin Density Modulation Near the Vortex Cores of Bi 2 Sr 2 CaCu 2 O 8+δ Andrew Mounce 1 , Sangwon Oh 1 , Sutirtha Mukhopadhyay 1 , William Halperin 1 , Arniel Reyes 2 , Phillip Kuhns 2 , Kazuhiro Fujita 3 , Motoyuki Ishikado 3 , Shin-Ichi Uchida 3 1 Northwestern University, Evanton, IL, USA 2 National High Magnetic Field Laboratory, Tallahassee, FL, USA 3 University of Tokyo, Tokyo, Japan Spatially resolved NMR spin-lattice (T 1 ) and spin-spin (T 2 ) measurements are used to probe the microscopic structure of the vortex lattice in the highly anisotropic High Temperature Superconductor Bi 2 Sr 2 CaCu 2 O 8+δ . Results, differing from similar measurements in YB 2 Cu 3 O 7 [1], are interpreted in the context of a long range spin density modulation in and outside the vortex core in accordance with previous LDOS "checkerboard" patterns found by STM[2]. Our model includes a checkerboard pattern of a Gaussian cosine decay from the vortex core, characterized by a amplitude and decay length, in addition to the diamagnetic contribution from vortices. Fitting this model to our data, we find that the amplitude increases and the decay length decreases with increasing external field and with this model we can also account for experimental T 1 relaxation rates. This work is supported by DOE/BES: DE-FG02-05ER46248 and the NHMFL by NSF and the State of Florida. [1] Mitrović, V.F. et.al. Nature 413, 501(2001) [2] Hoffman, J.E. et al. Science 295, 466 (2002)
O-29 38 NQR study of the phase segragation and sodium ordering in cobaltates Na x CoO 2 Irek Mukhamedshin 1 , Henri Alloul 2 , Alexander Dooglav 1 , Tatyana Platova 1 1 Kazan State University, 420008 Kazan, Russia 2 Université Paris-Sud, 91405 Orsay, France We have investigated a set of sodium cobaltate samples with various sodium content (0.67≤x≤0.75) using Nuclear Quadrupole Resonance (NQR) [1]. The four different stable phases and an intermediate one have been recognized. The NQR spectra of 59 Co allowed us to differentiate clearly the pure phase samples which could be easily distinguished from multi-phase ones. Systematic study of the Na 2/3 CoO 2 compound using 23 Na and 59 Co NQR and NMR [2,3], allowed us to establish reliably the atomic order of the Na layers and their stacking between the CoO 2 slabs. We give evidence that the Na + order stabilizes non magnetic Co 3+ ions on 25% of the cobalt sites arranged in a triangular sublattice. The transferred holes are delocalized on the 75% complementary cobalt sites which unexpectedly display a planar cobalt kagomé structure. These experimental results prove that both Curie- Weiss magnetism and metallic conductivity are provided by this kagomé sublattice of cobalt in sodium cobaltates. This study was partly supported by the RFBR under project #10-02- 01005. [1] T.A. Platova, et al., JETP Lett., 91 (2010) 457 [2] H. Alloul, et al., EPL 85 (2009) 47006 [3] T.A. Platova, et al., Phys. Rev. B 80 (2009) 224106
Page 1 and 2: ABSTRACT BOOK RECENT ADVANCES IN BR
Page 3 and 4: RECENT ADVANCES IN BROAD BAND SOLID
Page 9 and 10: INVITED LECTURES
Page 11 and 12: O-2 10 NMR in Quantum Spin Systems
Page 13 and 14: O-4 12 NMR and the quasi-one dimens
Page 15 and 16: O-7 14 NMR studies on the new iron
Page 17 and 18: O-9 16 NMR methods for investigatio
Page 19 and 20: O-10 18 Sodium cobaltates: A golden
Page 21 and 22: O-12 20 Broadband NMR at ultra high
Page 23 and 24: O-14 22 Strong Cu-O hybridization i
Page 25 and 26: O-16 24 Kagome Frustrated Antiferro
Page 27 and 28: O-18 26 Multiband Superconductivity
Page 29 and 30: O-20 28 Magnetic and physical prope
Page 31 and 32: O-21 30 NMR spin echo study of RF-I
Page 33 and 34: O-23 32 Clarification of Quantum Cr
Page 35 and 36: O-25 34 Nanoscale electronic order
Page 37: O-27 36 75 As NMR in Fe pnictide su
Page 41 and 42: O-31 40 NMR study of the Tomonaga-L
Page 43 and 44: POSTER CONTRIBUTIONS
Page 45 and 46: P-2 44 Cryogenic static and magic-a
Page 47 and 48: P-4 46 Nuclear Magnetic Resonance E
Page 49 and 50: P-6 48 Charge Induced Vortex Lattic
Page 51 and 52: P-8 50 77 Se NMR study of λ-(BETS)
Page 53 and 54: P-9 52 Electron spin relaxation in
Page 55 and 56: P-10 54 saturation field B c = 14.9
Page 57 and 58: P-12 56 Superionic Conductivity and
Page 59 and 60: P-14 58 NMR study of Quantum Critic
Page 61 and 62: P-16 60 Gap structure and vortex dy
Page 63 and 64: P-18 62 New Facility for Broadband
Page 65 and 66: P-20 64 Complex interplay of Ce 4f
Page 67 and 68: P-21 66 in our experiment. However,
Page 69 and 70: P-23 68 Observation of the Fermi Li
Page 71 and 72: P-25 70 Magnetic-field induced phas

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