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The breaking of orbital degeneracy on a transition metal cation and the resulting unequal electronic occupations of these orbitals provide a powerful lever over electron density and spin ordering in metal oxides. Here, we use ab initio calculations to show that reversibly modulating the orbital populations on Mn atoms can be achieved at ferroelectric/manganite interfaces by the presence of ferroelectric polarization on the nanoscale. The change in orbital occupation can be as large as 10%, greatly exceeding that of bulk manganites. This reversible orbital splitting is in large part controlled by the propagation of ferroelectric polar displacements into the interfacial region, a structural motif absent in the bulk and unique to the interface. We use epitaxial thin film growth and scanning transmission electron microscopy to verify this key interfacial polar distortion and discuss the potential of reversible control of orbital polarization via nanoscale ferroelectrics.
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http://dx.doi.org/10.1021/nl501209p | DOI Listing |
Phys Rev Lett
August 2025
University of Southern Denmark, Centre for Nano Optics, Campusvej 55, Odense M DK-5230, Denmark.
Controlling the spontaneous emission of nanoscale quantum emitters (QEs) is crucial for developing advanced photon sources required in many areas of modern nanophotonics, including quantum information technologies. Conventional approaches to shaping photon emission are based on using bulky configurations, while approaches recently developed in quantum metaphotonics suffer from limited capabilities in achieving desired polarization states and directionality, failing to provide on-demand photon sources tailored precisely to technological needs. Here, we propose a universal approach to designing versatile photon sources using on-chip QE-coupled meta-optics that enable direct transformations of QE-excited surface plasmon polaritons into spatially propagating photon streams with arbitrary polarization states, directionality, and amplitudes via both resonance and geometric phases supplied by scattering meta-atoms.
View Article and Find Full Text PDFJ Synchrotron Radiat
November 2025
State Key Laboratory of Chemical Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.
This study develops an integrated X-ray absorption spectroscopy (XAS) photoemission electron microscopy (PEEM) platform on beamline BL09U at the Shanghai Synchrotron Radiation Facility (SSRF), enabling nanoscale characterization of complex materials through energy-resolved imaging and local-area XAS. By using the wide range of energy tunability, full access to different polarizations and PEEM's surface sensitivity, we have established a gap-monochromator control system under the EPICS framework to synchronize the elliptically polarized undulator (EPU) gap and monochromator energy dynamically, optimizing photon flux stability for absorption fine structure analysis. Combining X-ray magnetic circular dichroism (XMCD) and X-ray magnetic linear dichroism (XMLD) with PEEM and local-area XAS, this platform achieves concurrent mapping of electronic structures and magnetic domains in ferromagnetic nano-patterns, as demonstrated through our studies of NiFe Permalloy using this system.
View Article and Find Full Text PDFNanoscale
September 2025
Research Center for Analytical Sciences, Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China.
Correction for 'Carbon dots with tunable dual emissions: from the mechanism to the specific imaging of endoplasmic reticulum polarity' by E. Shuang , , 2020, , 6852-6860, https://doi.org/10.
View Article and Find Full Text PDFDalton Trans
September 2025
Department of Chemistry & Biochemistry, University of Maryland Baltimore County, Baltimore, MD 21250, USA.
Two-dimensional van der Waals (2D-vdW) semiconducting ferroelectrics, such as CuInPSe (CIPSe) and CuInPS (CIPS), offer unique opportunities for lightweight, scalable, low-power nanoscale electronic devices. However, the limited pool of functional 2D-vdW ferroics highlights the need for clear design principles that can be used to guide experiments. Here, we use first-principles density functional theory (DFT) to study how isovalent atomistic substitution at In and P sites modifies structure, polarization, and electronic properties in CIPSe and CIPS.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
Hefei National Research Center for Physical Sciences at the Microscale, School of Chemistry and Materials Science, State Key Laboratory of Precision and Intelligent Chemistry, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230026, China.
The construction of C─N bonds from simple precursors under ambient conditions is a fundamental challenge in green chemistry, especially when it comes to avoiding energy-intensive protocols. Here, we present a continuous flow photocatalytic platform that enables the efficient coupling of C─N bonds between methanol and ammonia at ambient temperature and pressure. By synergistically engineering a Pd clusters-decorated TiO photocatalyst (1Pd/TiO) and a mass transfer-enhanced gas-liquid-solid Taylor flow reactor, the system achieves a remarkable formamide productivity of 256.
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