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We fabricate and measure electrically-gated tunnel junctions in which the insulating barrier is a sliding van der Waals ferroelectric made from parallel-stacked bilayer hexagonal boron nitride and the electrodes are single-layer graphene. Despite the nominally-symmetric tunnel-junction structure, these devices can exhibit substantial electroresistance upon reversing the ferroelectric polarization. The magnitude and sign of tunneling electroresistance are tunable by bias and gate voltage. We show that this behavior can be understood within a simple tunneling model that takes into account the quantum capacitance of the graphene electrodes, so that the tunneling densities of states in the electrodes are separately modified as a function of bias and gate voltage. 

Abstract Strain modulation is a crucial way in engineering nanoscale materials. It is even more important for single photon emitters in layered materials, where strain can trap a delocalized exciton, leading to quantum emission. Herein, we apply strain by using the piezoelectric relaxor ferroelectric substrate. In addition to the strain-tuning of energy and polarization, we report on new observations, including the enhanced polarizability and tunable diamagnetic shift, from the charged localized excitons. As indicated from the polarization-resolved measurements, we attribute the formation of charged localized excitons to selenium vacancy defects. The shallow defect trap, supported by the value of g-factor, further allows for strain-modulation of the electron-hole overlap, hence resulting in the tunable diamagnetic shift. Our results provide a new perspective in integrating layered materials with functional substrates. The contrasting features observed from the charged localized excitons also signify the prospect of charged localized emitters for quantum science and technology. 

Centromeres are essential for chromosome function, yet their role in shaping genome evolution in polyploid plants remains poorly understood. Allopolyploidy, where post-hybridization genome doubling merges parental genomes that may differ markedly in chromosomal architecture, has the potential to increase centromeric complexity and influence genomic plasticity. We explore this possibility in carnivorous Caryophyllales, a morphologically and chromosomally diverse plant lineage encompassing sundews, Venus flytraps, and Nepenthes pitcher plants. Focusing on sundews (Drosera), we generated chromosome-scale assemblies of holocentric D. regia and monocentric D. capensis, which share an allohexaploid origin but have diverged dramatically in genome structure. D. regia retains ancestral chromosomal fusions, dispersed centromeric repeats, and conserved synteny, whereas D. capensis exhibits extensive chromosomal reorganization and regionally localized centromeres after a lineage-specific genome duplication. Phylogenomic evidence traces D. regia to an ancient hybridization between sundew- and Venus flytrap-like ancestors, setting it apart within its infrageneric context. Genus-wide satellite DNA repeat profiling reveals rapid turnover and species-level variation in centromere organization. Together, these results establish sundews as a natural system for investigating how centromere dynamics interact with recurrent polyploidization and episodes of ecological innovation to shape genomic resilience. 

We devise a novel formulation and propose the concept of modal participation factors to nonlinear dynamical systems. The original definition of modal participation factors (or simply participation factors) provides a simple yet effective metric. It finds use in theory and practice, quantifying the interplay between states and modes of oscillation in a linear time-invariant (LTI) system. In this paper, with the Koopman operator framework, we present the results of participation factors for nonlinear dynamical systems with an asymptotically stable equilibrium point or limit cycle. We show that participation factors are defined for the entire domain of attraction, beyond the vicinity of an attractor, where the original definition of participation factors for LTI systems is a special case. Finally, we develop a numerical method to estimate participation factors using time series data from the underlying nonlinear dynamical system. The numerical method can be implemented by leveraging a well-established numerical scheme in the Koopman operator framework called dynamic mode decomposition. 

Abstract We elucidate the requirements for quantum operations that achieve environment-assisted invariance (envariance), a symmetry of entanglement. While envariance has traditionally been studied within the framework of local unitary operations, we extend the analysis to consider non-unitary local operations. First, we investigate the conditions imposed on operators acting on pure bipartite entanglement to attain envariance. We show that the local operations must take a direct-sum form in their Kraus operator representations, establishing decoherence-free subspaces. Furthermore, we prove that this also holds for the multipartite scenario. As an immediate consequence, we demonstrate that environment-assisted shortcuts to adiabaticity cannot be achieved through non-unitary operations. In addition, we show that the static condition of the eternal black hole in AdS/CFT is violated when the CFTs are coupled to the external baths. 

Abstract AB-stacked bilayer graphene has emerged as a fascinating yet simple platform for exploring macroscopic quantum phenomena of correlated electrons. Under large electric displacement fields and near low-density van-Hove singularities, it exhibits a phase with features consistent with Wigner crystallization, including negative dR/dT and nonlinear bias behavior. However, direct evidence for the emergence of an electron crystal at zero magnetic field remains elusive. Here, we explore low-frequency noise consistent with depinning and sliding of a Wigner crystal or solid. At large magnetic fields, we observe enhanced noise at low bias current and a frequency-dependent response characteristic of depinning and sliding, consistent with earlier scanning tunnelling microscopy studies confirming Wigner crystallization in the fractional quantum Hall regime. At zero magnetic field, we detect pronounced AC noise whose peak frequency increases linearly with applied DC current—indicative of collective electron motion. These transport signatures pave the way toward confirming an anomalous Hall crystal.