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We use transport and neutron-scattering measurements to show that a magnetic-field-induced transition from noncollinear to collinear spin arrangement in adjacent CuO_{2} planes of lightly electron-doped Pr_{1.3-x}La_{0.7}Ce_{x}CuO_{4} (x=0.01) crystals affects significantly both the in-plane and out-of-plane resistivity. In the high-field collinear state, the magnetoresistance (MR) does not saturate, but exhibits an intriguing four-fold-symmetric angular dependence, oscillating from being positive at B//[100] to being negative at B//[110]. The observed MR of more than 30% at low temperatures induced by a modest modification of the spin structure indicates an unexpectedly strong spin-charge coupling in electron-doped cuprates.
The pairing state symmetry of the electron-doped cuprate superconductors is thought to be s-wave in nature, in contrast with their hole-doped counterparts which exhibit a d-wave symmetry. We re-examine this issue based on recent improvements in our e
It was recently demonstrated that the anisotropic phonon heat transport behavior is a good probe of the stripe formation in La_{2-x}Sr_xCuO_4 (LSCO) [X. F. Sun {it et al.}, Phys. Rev. B {bf 67}, 104503 (2003)]. Using this probe, we examined an electr
We present a detailed temperature-dependent Raman light scattering study of optical phonons in molecular-beam-epitaxy-grown films of the electron-doped superconductor La_{2-x}Ce_{x}CuO_{4} close to optimal doping (x ~ 0.08, T_c = 29 K and x ~ 0.1, T_
Superstructure reflections due to the ordering of holes into stripes in La_(1.45)Nd_(0.4)Sr_(0.15)CuO_4 have been studied with high energy x-ray diffraction. These reflections have been observed clearly for the first time in a sample which is superco
For electron-doped cuprates, the strong suppression of antiferromagnetic spin correlation by efficient reduction annealing by the protect-annealing method leads to superconductivity not only with lower Ce concentrations but also with higher transitio