Publications de Johan Juul Chang

Search for relativistic fractionally charged particles in space

Jennifer Maria Frieden, Chiara Perrina, Jian Wang, Zhirui Xu, Yi Zhang, Siyuan Wang, Songmei Wu, Junqiu Liu, Johan Juul Chang, Jie Chen

More than a century after the performance of the oil drop experiment, the possible existence of fractionally charged particles (FCPs) still remains unsettled. The search for FCPs is crucial for some extensions of the Standard Model in particle physics. Mos ...

American Physical Society2022

Pseudogap suppression by competition with superconductivity in La-based cuprates

Johan Juul Chang, Claudia Giuseppina Fatuzzo

We carried out a comprehensive high-resolution angle-resolved photoemission spectroscopy (ARPES) study of the pseudogap interplay with superconductivity in La-based cuprates. The three systems La2-xSrxCuO4, La1.6-xNd0.4SrxCuO4, and La1.8-xEu0.2SrxCuO4 disp ...

AMER PHYSICAL SOC2022

Decoupling of lattice and orbital degrees of freedom in an iron-pnictide superconductor

László Forró, Qian Wang, Sergiy Katrych, Johan Juul Chang

The interplay between structural and electronic phases in iron-based superconductors is a central theme in the search for the superconducting pairing mechanism. While electronic nematicity is competing with superconductivity, the effect of purely structura ...

AMER PHYSICAL SOC2021

Resonant inelastic x-ray scattering study of Ca3Ru2O7

Qian Wang, Claudia Giuseppina Fatuzzo, Thorsten Schmitt, Johan Juul Chang, Yi Tseng

We present a combined oxygen K-edge x-ray absorption spectroscopy and resonant inelastic x-ray scattering (RIXS) study of the bilayer ruthenate Ca3Ru2O7. Our RIXS experiments on Ca3Ru2O7 were carried out on the overlapping planar and interplanar oxygen res ...

AMER PHYSICAL SOC2020

Orbitally selective breakdown of Fermi liquid quasiparticles in Ca1.8Sr0.2RuO4

Marco Grioni, Johan Juul Chang, Gianmarco Gatti

We present a comprehensive angle-resolved photoemission spectroscopy study of Ca1.8Sr0.2RuO4. Four distinct bands are revealed and along the Ru-O bond direction their orbital characters are identified through a light polarization analysis and comparison to ...

AMER PHYSICAL SOC2019

Strain-engineering Mott-insulating La2CuO4

Henrik Moodysson Rønnow, Noore Elahi Shaik, Thorsten Schmitt, Johan Juul Chang, Yu-Pei Tseng, Yi Tseng

The transition temperature T-c of unconventional superconductivity is often tunable. For a monolayer of FeSe, for example, the sweet spot is uniquely bound to titanium-oxide substrates. By contrast for La2-xSrxCuO4 thin films, such substrates are sub-optim ...

Nature Research2019

Time-Reversal Symmetry Breaking in Re-Based Superconductors

Joël Mesot, Johan Juul Chang

To trace the origin of time-reversal symmetry breaking (TRSB) in Re-based superconductors, we performed comparative muon-spin rotation and relaxation (mu SR) studies of superconducting noncentrosymmetric Re0.82Nb0.18 (T-c = 8.8 K) and centrosymmetric Re (T ...

AMER PHYSICAL SOC2018

Direct observation of orbital hybridisation in a cuprate superconductor

Thorsten Schmitt, Johan Juul Chang, Martin Mansson, Claudia Giuseppina Fatuzzo

Nature Publishing Group2018

Dispersive magnetic and electronic excitations in iridate perovskites probed by oxygen K-edge resonant inelastic x-ray scattering

Henrik Moodysson Rønnow, Thorsten Schmitt, Johan Juul Chang, Sara Fatale

2018

Nodeless superconductivity in the cage-type superconductor Sc5Ru6Sn18 with preserved time-reversal symmetry

Johan Juul Chang

2018