Fig. 2: Anisotropy and the in-plane resistivity for different T and H⊥.
From: Pair density wave at high magnetic fields in cuprates with charge and spin orders
The color map in a and b shows ρc/ρab in La1.8−xEu0.2SrxCuO4 (LESCO) with x = 0.10 (data from Fig. 1c) and La1.6−xNd0.4SrxCuO4 (LNSCO) with x = 0.12, respectively. Black squares: Tc(H⊥); ρab = 0 for all T < Tc(H⊥). Green dots: Hpeak(T), i.e. fields above which the in-plane MR changes from positive to negative; it has been established23 that Hpeak(T) ~ Hc2(T), i.e. the upper critical field. The error bars reflect the uncertainty in defining the MR peak within our experimental resolution (see inset of Supplementary Fig. 2a for an example; also see Supplementary Fig. 6a and ref. 23 for the raw MR data). Pink dots: Hp(T), the layer decoupling field; red triangles: Hb(T), where SC correlations are established in the planes as the SC transition is approached from the normal state. ρab(T) of c La1.7Eu0.2Sr0.1CuO4 and d La1.48Nd0.4Sr0.12CuO4 for several H⊥, as shown. Open symbols in c show the data from another run. Short-dashed lines guide the eye. The Hb(T) values obtained from the anisotropy are represented by the black dashed lines, as shown. The lower black dashed line in c corresponds to the layer decoupling field, Hp(T). In d, Hp(T) ≳ Hc(T) [or Tc(H⊥)]. Black arrows in c and d show that the splitting of the ρab(T) curves for different H⊥ becomes pronounced when R□/layer ≈ RQ = h/(2e)2.
