Person

Johan Juul Chang

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Related publications (44)

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The electronic structure of the high-symmetry perovskite iridate Ba2IrO4

Henrik Moodysson Rønnow, Marco Grioni, Johan Juul Chang, Luca Moreschini, Simon Karl Moser, Bastien Dalla Piazza

We report angle-resolved photoemission (ARPES) measurements, density functional and model tight-binding calculations on Ba2IrO4 (Ba-214), an antiferromagnetic (T-N = 230 K) insulator. Ba-214 does not exhibit the rotational distortion of the IrO6 octahedra ...

Institute of Physics (IoP) and Deutsche Physikalische Gesellschaft2014

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Using angle-resolved photoemission spectroscopy, we show that the recently discovered surface state on SrTiO3 consists of nondegenerate t(2g) states with different dimensional characters. While the d(xy) bands have quasi-2D dispersions with weak k(z) depen ...

Amer Physical Soc2014

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The influence of dimensionality on the electronic properties of layered perovskite materials remains an outstanding issue. We address it here for Sr3Ir2O7, the bilayer compound of the iridate Srn+1IrnO3n+1 series. By angle-resolved photoemission spectrosco ...

Amer Physical Soc2014

To explore the doping dependence of the recently discovered charge-density-wave (CDW) order in YBa2Cu3Oy, we present a bulk-sensitive high-energy x-ray study for several oxygen concentrations, including strongly underdoped YBa2Cu3O6.44. Combined with previ ...

Amer Physical Soc2014

Nodal Landau Fermi-liquid quasiparticles in overdoped La1.77Sr0.23CuO4

Henrik Moodysson Rønnow, Marco Grioni, Joël Mesot, Johan Juul Chang, Martin Mansson, Claudia Giuseppina Fatuzzo

Nodal angle-resolved photoemission spectra taken on overdoped La1.77Sr0.23CuO4 are presented and analyzed. It is proven that the low-energy excitations are true Landau Fermi-liquid quasiparticles. We show that momentum and energy distribution curves can be ...

Amer Physical Soc2014

Glassy low-energy spin fluctuations and anisotropy gap in La1.88Sr0.12CuO4

Henrik Moodysson Rønnow, Joël Mesot, Johan Juul Chang

We present high-resolution triple-axis neutron scattering studies of the high-temperature superconductor La1.88Sr0.12CuO4 (Tc=27 K). The temperature dependence of the low-energy incommensurate magnetic fluctuations reveals distinctly glassy features. The g ...

American Physical Society2013

Evolution from a Nodeless Gap to d(x2-y2)-Wave in Underdoped La2-xSrxCuO4

Joël Mesot, Johan Juul Chang, Elia Razzoli

Using angle-resolved photoemission spectroscopy (ARPES), it is revealed that the low-energy electronic excitation spectra of highly underdoped superconducting and nonsuperconducting La2-xSrxCuO4 cuprates are gapped along the entire underlying Fermi surface ...

Amer Physical Soc2013

X-ray diffraction measurements show that the high-temperature superconductor YBa2Cu3O6.54, with ortho-II oxygen order, has charge-density-wave order in the absence of an applied magnetic field. The dominant wave vector of the charge density wave is q(CDW) ...

Amer Physical Soc2013

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High-temperature superconductivity emerges from an un-conventional metallic state. This has stimulated strong efforts to understand exactly how Fermi liquids breakdown and evolve into an un-conventional metal. A fundamental question is how Fermi liquid qua ...

Nature Publishing Group2013

Glassy low-energy spin fluctuations and anisotropy gap in La_{1.88}Sr_{0.12}CuO_{4}

Joël Mesot, Johan Juul Chang, Christopher Werner Matthias Robeller

We present high-resolution triple-axis neutron scattering studies of the high-temperature superconductor La1.88Sr0.12CuO4 (T-c = 27 K). The temperature dependence of the low-energy incommensurate magnetic fluctuations reveals distinctly glassy features. Th ...

Amer Physical Soc2013