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تسجيل مستخدم جديدFermi surface transformation at the pseudogap critical point of a cuprate superconductor
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The nature of the pseudogap phase remains a major barrier to our understanding of cuprate high-temperature superconductivity. Whether or not this metallic phase is defined by any of the reported broken symmetries, the topology of its Fermi surface remains a fundamental open question. Here we use angle-dependent magnetoresistance (ADMR) to measure the Fermi surface of the cuprate Nd-LSCO. Above the critical doping $p^*$---outside of the pseudogap phase---we fit the ADMR data and extract a Fermi surface geometry that is in quantitative agreement with angle-resolved photoemission. Below $p^*$---within the pseudogap phase---the ADMR is qualitatively different, revealing a clear transformation of the Fermi surface. Changes in the quasiparticle lifetime across $p^*$ are ruled out as the cause of this transformation. Instead we find that our data are most consistent with a reconstruction of the Fermi surface by a $Q=(pi, pi)$ wavevector.
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We report measurements of the Seebeck effect in both the $ab$ plane ($S_{rm a}$) and along the $c$ axis ($S_{rm c}$) of the cuprate superconductor La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_4$ (Nd-LSCO), performed in magnetic fields large enough to suppress
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The electrical resistivity $rho$ and Hall coefficient R$_H$ of the tetragonal single-layer cuprate Nd-LSCO were measured in magnetic fields up to $H = 37.5$ T, large enough to access the normal state at $T to 0$, for closely spaced dopings $p$ across
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