Seebeck coefficient in a cuprate superconductor: particle-hole asymmetry in the strange metal phase and Fermi surface transformation in the pseudogap phase

Abstract

We report measurements of the Seebeck effect in both the $ab$ plane ($S_{\mathrm{a}}$) and along the $c$ axis ($S_{\mathrm{c}}$) 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 superconductivity down to low temperature. We use the Seebeck coefficient as a probe of the particle-hole asymmetry of the electronic structure across the pseudogap critical doping $p^{\star }=0.23$. Outside the pseudogap phase, at $p=0.24>p^{\star }$, we observe a positive and essentially isotropic Seebeck coefficient as $T\to 0$. That $S>0$ at $p=0.24$ is at odds with expectations given the electronic band structure of Nd-LSCO above $p^{\star }$ and its known electron-like Fermi surface. We can reconcile this observation by invoking an energy-dependent scattering rate with a particle-hole asymmetry, possibly rooted in the non-Fermi liquid nature of cuprates just above $p^{\star }$. Inside the pseudogap phase, for $p<p^{\star }$, $S_{\mathrm{a}}$ is seen to rise at low temperature as previously reported, consistent with the drop in carrier density $n$ from $n\simeq 1+p$ to $n\simeq p$ across $p^{\star }$ as inferred from other transport properties. In stark contrast, $S_{\mathrm{c}}$ at low temperature becomes negative below $p^{\star }$, a novel signature of the pseudogap phase. The sudden drop in $S_{\mathrm{c}}$ reveals a change in the electronic structure of Nd-LSCO upon crossing $p^{\star }$. We can exclude a profound change of the scattering across $p^{\star }$ and conclude that the change in the out-of-plane Seebeck coefficient originates from a transformation of the Fermi surface.

12 pages, 12 figures

References in corpus (9)

• On the thermoelectricity of correlated electrons in the zero-temperature limit
• How bad metals turn good: spectroscopic signatures of resilient quasiparticles
• Giant thermal Hall conductivity from neutral excitations in the pseudogap phase of cuprates
• Low-Energy Electronic Structure of the High-Tc Cuprates La2-xSrxCuO4 Studied by Angle-resolved Photoemission Spectroscopy
• Phenomenological theories of the low-temperature pseudogap: Hall number, specific heat and Seebeck coefficient
• Thermopower across the phase diagram of the cuprate La${}_{1.6-x}$Nd${}_{0.4}$Sr${}_x$CuO${}_4$ : signatures of the pseudogap and charge-density-wave phases
• Skewed Non-Fermi Liquids and the Seebeck Effect
• The Seebeck coefficient in correlated low dimensional organic metals
• Positive Seebeck coefficient in highly doped La${}_{2-x}$Sr${}_x$CuO${}_4$ ($x$=0.33); its origin and implication

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