Layers split and zip for phase transition
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Liability of origin imprints: how do the origin imprints influence corporate innovation? Evidence from China
In transforming emerging economies, many state-owned enterprises (SOEs) underwent privatization, transferring property rights from the state to private entities. This transition not only facilitated the establishment of entrepreneurial family firms but also encouraged the emergence of privatized family firms as property rights were transferred to individuals and families. Consequently, the roots of property rights in these settings can be traced back to either direct establishment or privatization. In this study, we examine how these origin imprints influence corporate innovation. By analyzing a dataset of A-share Chinese listed non-financial family firms spanning from 2005 to 2021, we find that pre-privatization organizational imprints which primarily focus on societal well-being, tend to persist within these privatized family firms, resulting in a lower degree of corporate innovation compared to their entrepreneurial counterparts. Moreover, additional subsample analysis indicates that the adverse impact of privatized family firms on corporate innovation is intensified by strong political connections while mitigated by a well-developed institutional environment in the region. Our results are robust to various econometric methods, alternative explanations, and approaches to address endogeneity concerns such as the two-stage least squares (2SLS), Generalized Method of Moments (GMM), and propensity score matching (PSM) techniques. Overall, this study highlights a source of heterogeneity within the family firms and reveals how organizational imprints inherited from a pre-privatization economic regime can diminish the positive effects usually associated with family ownership.
Sub-minute synthesis and modulation of β/λ-MxTi3-xO5 ceramics towards accessible heat storage
Nearly 50% of global primary energy consumption is lost as low-temperature heat. λ-Ti3O5 holds promise for waste heat harvesting and reuse; however, achieving reversible phase transitions between its λ and β phases under accessible conditions remains a major challenge. Here, we proposed a simple laser method that incorporates element substitution for sub-minute synthesis (20–60 s) of λ-MxTi3-xO5 (M = Mg, Al, Sc, V, Cr, Mn, or Fe, 0.09 ≤ x ≤ 0.42). In particular, aluminum-substituted λ-AlxTi3-xO5 demonstrated the lowest energy barrier, with a transition pressure of 557 MPa and temperature of 363 K. Notably, compression of the (001) crystal plane could reduce the transition pressure to only 35–40 MPa, enabling the applicability of λ-AlxTi3-xO5 for wide applications in heat recovery and future lunar explorations.
Ultrafast exciton-phonon coupling and energy transfer dynamics in quasi-2D layered Ruddlesden-Popper perovskites
Understanding the performance of perovskite solar cells is critical for advancing sustainable energy solutions. Hot-drop casted quasi-2D Ruddlesden-Popper perovskites (RPPs) exhibit remarkable efficiency and stability, making them promising for commercial applications. However, the ultrafast energy transfer and exciton-phonon interactions in these materials remain unclear. Here, we show that using advanced techniques like two-dimensional electronic spectroscopy (2DES) and transient grating (TG), we can unravel energy dynamics in hot-drop casted RPP films. Our study reveals rapid energy transfer between perovskite layers occurring within 100–220 femtoseconds and highlights how exciton-phonon coupling drives structural changes in the material. Coherent vibrational signals identify key lattice and organic cation modes, providing insights into their role in energy dissipation. These findings deepen our understanding of how 2D perovskites work and pave the way for improving the efficiency and stability of next-generation optoelectronic devices.
Switching on and off the spin polarization of the conduction band in antiferromagnetic bilayer transistors
Antiferromagnetic conductors with suitably broken spatial symmetries host spin-polarized bands, which lead to transport phenomena commonly observed in metallic ferromagnets. In bulk materials, it is the given crystalline structure that determines whether symmetries are broken and spin-polarized bands are present. Here we show that, in the two-dimensional limit, an electric field can control the relevant symmetries. To this end, we fabricate a double-gate transistor based on bilayers of van der Waals antiferromagnetic semiconductor CrPS4 and show how a perpendicular electric displacement field can switch the spin polarization of the conduction band on and off. Because conduction band states with opposite spin polarizations are hosted in the different layers and are spatially separated, these devices also give control over the magnetization of the electrons that are accumulated electrostatically. Our experiments show that double-gated CrPS4 transistors provide a viable platform to create gate-induced conductors with near unity spin polarization at the Fermi level, as well as devices with a full electrostatic control of the total magnetization of the system.
Controlling Coulomb correlations and fine structure of quasi-one-dimensional excitons by magnetic order
Many surprising properties of quantum materials result from Coulomb correlations defining electronic quasiparticles and their interaction chains. In van der Waals layered crystals, enhanced correlations have been tailored in reduced dimensions, enabling excitons with giant binding energies and emergent phases including ferroelectric, ferromagnetic and multiferroic orders. Yet, correlation design has primarily relied on structural engineering. Here we present quantitative experiment–theory proof that excitonic correlations can be switched through magnetic order. By probing internal Rydberg-like transitions of excitons in the magnetic semiconductor CrSBr, we reveal their binding energy and a dramatic anisotropy of their quasi-one-dimensional orbitals manifesting in strong fine-structure splitting. We switch the internal structure from strongly bound, monolayer-localized states to weakly bound, interlayer-delocalized states by pushing the system from antiferromagnetic to paramagnetic phases. Our analysis connects this transition to the exciton’s spin-controlled effective quantum confinement, supported by the exciton’s dynamics. In future applications, excitons or even condensates may be interfaced with spintronics; extrinsically switchable Coulomb correlations could shape phase transitions on demand.
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