When discussing atomic nuclei,deformation is one of the most common topics.However,when we connect the concept of shape with high-precision experimental measurements,sometimes the explanation may not be as simple as w...When discussing atomic nuclei,deformation is one of the most common topics.However,when we connect the concept of shape with high-precision experimental measurements,sometimes the explanation may not be as simple as we think.A recent measurement of nuclear charge radii(Phys.Rev.Lett.134,182501(2025))challenges current nuclear ab initio models.展开更多
Recent theoretical work has predicted the existence of a“dipole spiral”structure in strained freestanding membranes of PbTiO_(3),suggesting a potential route to enhanced electromechanical responses[Phys.Rev.Lett.133...Recent theoretical work has predicted the existence of a“dipole spiral”structure in strained freestanding membranes of PbTiO_(3),suggesting a potential route to enhanced electromechanical responses[Phys.Rev.Lett.133046802(2024)].However,its microscopic nature,energetic landscape,and electronic properties remain largely unexplored from a first-principles perspective.Here,using density functional theory on PbTiO3 under biaxial tensile strain,we identify a novel form of polar order:a chiral,non-collinear ferroelectric double helix.We find that two distinct,intertwined polarization helices are formed by the local Pb-O and Ti-O dipoles,reminiscent of DNA.This topology is stabilized by a collective helical twisting of the encompassing oxygen cages(the polyhedra for both Pb and Ti cations),which gives rise to an electric Dzyaloshinskii–Moriya-like interaction.The resulting structure,which can be conceptualized as a“self-moiré”crystal,exhibits two coupled functionalities.First,it possesses a rotational pseudo-zero-energy mode that underpins a giant piezoelectric response(e_(33)≈16C/m^(2)).Second,the long-period potential reconstructs the electronic band structure,leading to a multi-valley electronic topology at the valence band edge.Our work establishes a physical route to designing complex chiral order that supports both giant electromechanical coupling and multi-valley electronics.展开更多
The recently observed two-photon Landau-Zener-Stückelberg-Majorana(LZSM)effect in superconducting circuits[Phys.Rev.Lett.134060602(2025)]has provided a robust pathway for high-fidelity population transfer in qudi...The recently observed two-photon Landau-Zener-Stückelberg-Majorana(LZSM)effect in superconducting circuits[Phys.Rev.Lett.134060602(2025)]has provided a robust pathway for high-fidelity population transfer in qudit systems,but its adiabatic nature necessitates long operation times,which are vulnerable to decoherence.展开更多
基金supported by the National Natural Science Foundation of China(No.12235003).
文摘When discussing atomic nuclei,deformation is one of the most common topics.However,when we connect the concept of shape with high-precision experimental measurements,sometimes the explanation may not be as simple as we think.A recent measurement of nuclear charge radii(Phys.Rev.Lett.134,182501(2025))challenges current nuclear ab initio models.
基金supported by Zhejiang Provincial Natural Science Foundation of China(Grant No.LR25A040004)。
文摘Recent theoretical work has predicted the existence of a“dipole spiral”structure in strained freestanding membranes of PbTiO_(3),suggesting a potential route to enhanced electromechanical responses[Phys.Rev.Lett.133046802(2024)].However,its microscopic nature,energetic landscape,and electronic properties remain largely unexplored from a first-principles perspective.Here,using density functional theory on PbTiO3 under biaxial tensile strain,we identify a novel form of polar order:a chiral,non-collinear ferroelectric double helix.We find that two distinct,intertwined polarization helices are formed by the local Pb-O and Ti-O dipoles,reminiscent of DNA.This topology is stabilized by a collective helical twisting of the encompassing oxygen cages(the polyhedra for both Pb and Ti cations),which gives rise to an electric Dzyaloshinskii–Moriya-like interaction.The resulting structure,which can be conceptualized as a“self-moiré”crystal,exhibits two coupled functionalities.First,it possesses a rotational pseudo-zero-energy mode that underpins a giant piezoelectric response(e_(33)≈16C/m^(2)).Second,the long-period potential reconstructs the electronic band structure,leading to a multi-valley electronic topology at the valence band edge.Our work establishes a physical route to designing complex chiral order that supports both giant electromechanical coupling and multi-valley electronics.
基金supported by the National Natural Science Foundation of China(Grant Nos.12575032,62571494,12304407,and 12274376)the Natural Science Foundation of Henan Province(Grant No.232300421075)the China Postdoctoral Science Foundation(Grant Nos.2023TQ0310 and 2024M762973)。
文摘The recently observed two-photon Landau-Zener-Stückelberg-Majorana(LZSM)effect in superconducting circuits[Phys.Rev.Lett.134060602(2025)]has provided a robust pathway for high-fidelity population transfer in qudit systems,but its adiabatic nature necessitates long operation times,which are vulnerable to decoherence.
