Critical Doping for the Onset of Fermi-Surface Reconstruction by Charge-Density-Wave Order in the Cuprate SuperconductorLa2−xSrxCuO

Abstract

The Seebeck coefficient S of the cuprate superconductor La 2−x Sr x CuO 4 (LSCO) was measured in magnetic fields large enough to access the normal state at low temperatures, for a range of Sr concentrations from x ¼ 0.07 to x ¼ 0.15. For x ¼ 0.11, 0.12, 0.125, and 0.13, S=T decreases upon cooling to become negative at low temperatures. The same behavior is observed in the Hall coefficient R H ðTÞ. In analogy with other hole-doped cuprates at similar hole concentrations p, the negative S and R H show that the Fermi surface of LSCO undergoes a reconstruction caused by the onset of charge-density-wave modulations. Such modulations have indeed been detected in LSCO by x-ray diffraction in precisely the same doping range. Our data show that in LSCO this Fermi-surface reconstruction is confined to 0.085 < p < 0.15. We argue that in the field-induced normal state of LSCO, charge-density-wave order ends at a critical doping p CDW ¼ 0.15 AE 0.005, well below the pseudogap critical doping p ⋆ ≃ 0.19.

Fermi-surface transformation across the pseudogap critical point of the cuprate superconductor La1.6−xNd0.4SrxCuO4

“…In LSCO, the Seebeck coefficient in high field was used in similar fashion to pin down the endpoint of FSR, giving p CDW = 0.15 ± 0.005 [25]. This is again consistent with the fact that XRD detects no CDW modulations in LSCO at p = 0.15 [40].…”

“…This means that the critical doping for CDW order, p CDW = 0.16 ± 0.005, is distinctly lower than the pseudogap critical point, which in YBCO is located at p = 0.19 ± 0.01 [24]. A similar separation of normal-state critical points was also found in LSCO from high-field Seebeck measurements [25], with p CDW = 0.15 ± 0.005 and p = 0.18 [4]. The implication is that the pseudogap phase is distinct from the CDW phase.…”

Density Wave Probes Cuprate Quantum Phase Transition

“…In nearly all cuprate families, charge order in the form of disordered charge modulations have been reported in underdoped compounds, with detection terminating at [19] or before [6,20] the doping where the FS transition occurs. In (Bi,Pb) 2 (Sr,La) 2 CuO 6+δ , Bi2201, however, charge modulations extend into the overdoped regime [21,22].…”

Saturation of resistivity and Kohler's rule in Ni-dopedLa1.85Sr0.15CuO4cuprate

“…In contrast to overdoped cuprates where large cylindrical Fermi surface yields a carrier density n=p+1 (p being doping level) [11][12][13], the total volume of Fermi surface in underdoped systems is a small fraction of the first Brillouin zone and corresponds to n=p through Luttinger's theorem [14][15][16][17]. This small n should be reflected in zero-field transport.…”