arXiv subjects

D. Babich

Publications and source records attributed to D. Babich.

3 recordsLinked to original sources

arXiv2026

Selective coupling of coherent phonons to intertwined charge-orbital and magnetic orders in doped manganites

Strongly correlated materials feature technologically relevant functionalities such as high-temperature superconductivity and colossal magnetoresistance, which emerges from the competition and coexistence of electronic and magnetic phases. Uncovering the microscopic interactions underlying these phenomena remains challenging because spin, orbital, charge, and lattice degrees of freedom are inherently intertwined. Here, by combining time-resolved X-ray diffraction and polarization-resolved ultrafast optical reflectivity in La1/4Pr3/8Ca3/8MnO3, we reveal that coherent phonon modes can selectively track different ordered phases: the in-plane phonon response is predominantly sensitive to charge/orbital order, and the c-axis phonon response is sensitive to magnetic order. Moreover, a ferromagnetic-related hysteresis emerges even when solely probing the charge/orbital-ordered phase, indicating a strong microscopic coupling between the spatially separated charge/orbital-ordered and ferromagnetic-ordered phases. These results demonstrate that coherent phonons provide a direct time-domain route to disentangle intertwined electronic and magnetic dynamics in coupled phases.

cond-mat.str-el↗

arXiv2023

Coherent control of orbital wavefunctions in the quantum spin liquid $Tb_{2}Ti_{2}O_{7}$

Resonant driving of electronic transitions with coherent laser sources creates quantum coherent superpositions of the involved electronic states. Most time-resolved studies have focused on gases or isolated subsystems embedded in insulating solids, aiming for applications in quantum information. Here, we demonstrate coherent control of orbital wavefunctions in pyrochlore $Tb_{2}Ti_{2}O_{7}$, which forms an interacting spin liquid ground state. We show that resonant excitation with a strong THz pulse creates a coherent superposition of the lowest energy Tb 4f states before the magnetic interactions eventually dephase them. The coherence manifests itself as a macroscopic oscillating magnetic dipole, which is detected by ultrafast resonant x-ray diffraction. The induced quantum coherence demonstrates coherent control of orbital wave functions, a new tool for the ultrafast manipulation and investigation of quantum materials.

cond-mat.str-el↗

arXiv2021

Lattice contraction induced by resistive switching in chromium-doped V2O3: a hallmark of Mott physics

Since the beginnings of the electronic age, a quest for ever faster and smaller switches has been initiated, since this element is ubiquitous and foundational in any electronic circuit to regulate the flow of current. Mott insulators are promising candidates to meet this need as they undergo extremely fast resistive switching under electric field. However the mechanism of this transition is still under debate. Our spatially-resolved μ-XRD imaging experiments carried out on the prototypal Mott insulator (V0.95Cr0.05)2O3 show that the resistive switching is associated with the creation of a conducting filamentary path consisting in an isostructural compressed phase without any chemical nor symmetry change. This clearly evidences that the resistive switching mechanism is inherited from the bandwidth-controlled Mott transition. This discovery might hence ease the development of a new branch of electronics dubbed Mottronics.

cond-mat.str-el↗