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تسجيل مستخدم جديدStrange Metallic Transport in the Antiferromagnetic Regime of Electron Doped Cuprates
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We report magnetoresistance and Hall Effect results for electron-doped films of the high-temperature superconductor La$_{2-x}$Ce$_x$CuO$_4$ (LCCO) for temperatures from 0.7 to 45 K and magnetic fields up to 65 T. For x = 0.12 and 0.13, just below the Fermi surface reconstruction (FSR), the normal state in-plane resistivity exhibits a well-known upturn at low temperature. Our new results show that this resistivity upturn is eliminated at high magnetic field and the resistivity becomes linear-in-temperature from $sim$ 40 K down to 0.7 K. The magnitude of the linear coefficient scales with Tc and doping, as found previously [1,2] for dopings above the FSR. In addition, the normal state Hall coefficient has an unconventional field dependence for temperatures below 50K. This anomalous transport data presents a new challenge to theory and suggests that the strange metal normal state is also present in the antiferromagnetic regime.
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Strange metals possess highly unconventional transport characteristics, such as a linear-in-temperature ($T$) resistivity, an inverse Hall angle that varies as $T^2$ and a linear-in-field ($H$) magnetoresistance. Identifying the origin of these colle
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We study the quantum transition from an antiferromagnet to a superconductor in a model for electron- and hole-doped cuprates by means of a variational cluster perturbation theory approach. In both cases, our results suggest a tendency towards phase s
eparation between a mixed antiferromagnetic-superconducting phase at low doping and a pure superconducting phase at larger doping. However, in the electron-doped case the energy scale for phase separation is an order of magnitude smaller than for hole doping. We argue that this can explain the different pseudogap and superconducting transition scales in hole- and electron-doped materials.
Electron interactions are pivotal for defining the electronic structure of quantum materials. In particular, the strong electron Coulomb repulsion is considered the keystone for describing the emergence of exotic and/or ordered phases of quantum matt
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ivity. The accuracy of our approach is gauged by detailed comparisons with Quantum Monte Carlo simulations. The negative pressure dependence of Tc and the existence of photoemission hot spots in electron-doped cuprate superconductors find their natural explanation within this approach.
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