ترغب بنشر مسار تعليمي؟ اضغط هنا

Re-appearance of antiferromagnetic ordering with Zn and Ni substitution in La_{2-x}Sr_xCuO_4

79   0   0.0 ( 0 )
 نشر من قبل Yutaka Itoh
 تاريخ النشر 2003
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

The effects of nonmagnetic Zn and magnetic Ni substitution for Cu site on magnetism are studied by measurements of uniform magnetic susceptibility for lightly doped La_{2-x}Sr_xCu_{1-z}M_zO_4 (M=Zn or Ni) polycrystalline samples. For the parent x=0, Zn doping suppresses the N{e}el temperature T_N whereas Ni doping hardly changes T_N up to z=0.3. For the lightly doped samples with T_N~0, the Ni doping recovers T_N. For the superconducting samples, the Ni doping induces the superconductivity-to-antiferromagnetic transition (or crossover). All the heavily Ni doped samples indicate a spin glass behavior at ~15 K.



قيم البحث

اقرأ أيضاً

Magnetotransport measurements on the overdoped cuprate La_{1.7}Sr_{0.3}CuO_4 are fitted using the Ong construction and band parameters inferred from angle-resolved photoemission. Within a band picture, the low temperature Hall data can only be fitted satisfactorily by invoking strong basal-plane anisotropy in the mean-free-path $ell$. This violation of the isotropic-$ell$ approximation supports a picture of dominant small-angle elastic scattering in cuprates due to out-of-plane substitutional disorder. We show that both band anisotropy and anisotropy in the elastic scattering channel strongly renormalize the Hall coefficient in overdoped La_{2-x}Sr_xCuO_4 over a wide doping and temperature range.
Spin-glass magnetism confined to individual weakly interacting vortices is detected in two different families of high-transition-temperature (T_c) superconductors, but only in samples on the low-doping side of the low-temperature normal state metal-t o-insulator crossover (MIC). Our findings unravel the mystery of the MIC, but more importantly identify the true location of the field-induced quantum phase transition (QPT) in the superconducting state. The non-uniform appearance of magnetism in the vortex state favours a surprisingly exotic phase diagram, in which spatially inhomogeneous competing order is stabilized at the QPT, and an `avoided quantum critical point (QCP) is realized at zero magnetic field.
We present a study of the magnetic susceptibility in carefully detwinned La_{2-x}Sr_{x}CuO_4 single crystals in the lightly-doped region (x=0-0.03), which demonstrates a remarkable in-plane anisotropy of the spin system. This anisotropy is found to p ersist after the long-range antiferromagnetic (AF) order is destroyed by hole doping, suggesting that doped holes break the AF order into domains in which the spin alignment is kept essentially intact. It turns out that the freezing of the spins taking place at low temperatures is also notably anisotropic, implying that the spin-glass feature is governed by the domain structure as well.
393 - T. Adachi , N. Oki , Risdiana 2008
We have investigated effects of Zn and Ni on the Cu-spin dynamics and superconductivity from the zero-field muon-spin-relaxation (ZF-muSR) and magnetic-susceptibility, chi, measurements for La_2-x_Sr_x_Cu_1-y_(Zn,Ni)_y_O_4_ with x=0.15-0.20, changing y up to 0.10 in fine step. In the optimally doped x=0.15, it has been concluded that the formation of a magnetic order requires a larger amount of Ni than that of Zn, which is similar to our previous results of x=0.13. From the estimation of volume fractions of superconducting (SC) and magnetic regions, it has been found for x=0.15 that the SC region is in rough correspondence to the region where Cu spins fluctuate fast beyond the muSR frequency window for both Zn- and Ni-substituted samples. According to the stripe model, it follows that, even for x=0.15, the dynamical stripe correlations of spins and holes are pinned and localized around Zn and Ni, leading to the formation of the static stripe order and the suppression of superconductivity. These may indicate an importance of the dynamical stripe in the appearance of the high-T_c_ superconductivity in the hole-doped cuprates. In the overdoped regime of x=0.18 and 0.20, on the other hand, the SC region seems to be in rough correspondence to the region where Cu spins fluctuate fast beyond the muSR frequency window, though it appears that the Cu-spin dynamics and superconductivity are affected by the phase separation into SC and normal-state regions.
139 - V. Baledent , B. Fauque , Y. Sidis 2010
In high temperature copper oxides superconductors, a novel magnetic order associated with the pseudogap phase has been identified in two different cuprate families over a wide region of temperature and doping. We here report the observation below 120 K of a similar magnetic ordering in the archetypal cuprate ${rm La_{2-x}Sr_xCuO_4}$ (LSCO) system for x=0.085. In contrast to the previous reports, the magnetic ordering in LSCO is {itbf only} short range with an in-plane correlation length of $sim$ 10 AA and is bidimensional (2D). Such a less pronounced order suggests an interaction with other electronic instabilities. In particular, LSCO also exhibits a strong tendency towards stripes ordering at the expense of the superconducting state.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا