Hole doped transition metal oxides are famous due to their extraordinary charge transport properties, such as high temperature superconductivity (cuprates) and colossal magnetoresistance (manganites)1 . Astonishing, the mother system of these compounds is a Mott insulator 2 , whereas important role in the establishment of the metallic or superconducting state is played by the way that holes are self-organized with doping 2,3,4 . Experiments have shown that by adding holes the insulating phase breaks into antiferromagnetic (AFM) regions, which are separated by hole rich clumps (stripes) with a rapid change of the phase of the background spins and orbitals 2,5 . However, recent experiments in overdoped manganites of the La 1−x Ca x MnO 3 (LCMO) family have shown that instead of charge stripes 6,7,8 , charge in these systems is organized in a uniform charge density wave (CDW) 9,10,11 . Besides, recent theoretical works predicted that the ground state is inhomogeneously modulated by orbital and charge solitons 12,13 , i.e. narrow regions carrying charge ±e/2, where the orbital arrangement varies very rapidly. So far, this has been only a theoretical prediction. Here, by using 139 La Nuclear Magnetic Resonance (NMR) we provide direct evidence that the ground state of overdoped LCMO is indeed solitonic. By lowering temperature the narrow NMR spectra observed in the AFM phase are shown to wipe out, while for T < 30K a very broad spectrum reappears, characteristic of an incommensurate (IC) charge and spin modulation. Remarkably, by further decreasing temperature, a relatively narrow feature emerges from the broad IC NMR signal, manifesting the appearance of a solitonic modulation as T → 0.The presence of an IC spin-density modulation and the formation of charge stripes in AFM transition metal oxides was first observed in superconducting La 2−x Sr x CuO 4 and their insulating nickelate counterparts 14,15 . Inelastic neutron scattering experiments have shown that holes in these materials tend to localize into periodically arranged antiphase domain walls, separating AFM regions, which propagate diagonally through the CuO 2 (respectively NiO 2 ) layers 2 . In addition, a link between stripe ordering and the wipeout effect (disappearance) of the NMR/NQR signal was observed 16,17 , which indicates that most probably the stripe phase in these systems is a slowly fluctuating, strongly correlated fluid over an extended temperature range.In case of the LCMO family for x ≥ 0.5, electron diffraction experiments unveiled an IC charge modulation with wave vector q a ⋆6,7,8 , which is associated with orbital and AFM spin ordering. This charge modulation has been considered as signature of charge stripes arising from the ordered arrangement of alternating Mn +3 and Mn +4 ions. However, a number of recent experiments put into question this kind of Mn +3 and Mn +4 charge alternation 18,19 ; instead they suggest the formation of a charge modulation wave with a uniform periodicity for all x ≥ 0.5 9 . A collective sliding of the charge sys...
