arXiv subjects

J. L. de Boer

Publications and source records attributed to J. L. de Boer.

3 recordsLinked to original sources

arXiv2000

Response: Spin-Singlet clusters in the ladder compound NaV2O5

This response on a Comment on Reference 2 discusses the space group Fmm2 determination of the low temperature structure of NaV2O5. We show that while conventional crystallography is consistent with 'zig-zag' charge ordering of half of the ladders, recent spectroscopic measurements suggest that the symmetry is lower than Fmm2. We suggest space group C2, consistent with full 'zig-zag' charge ordering of all the ladders.

cond-mat.str-el↗

arXiv1999

Inversion symmetry in the spin-Peierls compound NaV2O5

At room-temperature NaV2O5 was found to have the centrosymmetric space group Pmmn. This space group implies the presence of only one kind of V site in contrast with previous reports of the non-centrosymmetric counterpart P21mn. This indicates a non-integer valence state of vanadium. Furthermore, this symmetry has consequences for the interpretation of the transition at 34 K, which was ascribed to a spin-Peierls transition of one dimensional chains of V4+.

cond-mat.str-el↗

arXiv1998

Global and Local Measures of the Intrinsic Josephson Coupling in Tl2Ba2CuO6

The Intlerlayer Josephson coupling between the planes of Tl2Ba2CuO6 was determined using infrared spectroscopy and magnetic flux vortex imaging. These methods give a consistent value of $ω_J$= 28 cm$^{-1}$ which, when combined with the condensation energy produces a discrepancy of at least an order of magnitude with deductions based on the interlayer tunneling model.

cond-mat.str-el↗