Scholarlink

<p>Strain gradients can significantly redistribute electron charge density, thereby inducing net dipole moments and generating higher-order electromechanical interactions in materials. These effects give rise to the novel concepts of higher-order quantum stress and quantum couple stress, which have not yet been systematically explored within a rigorous quantum mechanical framework. Understanding such higher-order phenomena is particularly important at nanometer and sub-micron length scales, where strain gradient effects become increasingly pronounced and classical continuum theories often lose predictive capability. In this work, we develop a rigorous theory of higher-order quantum stress within the framework of density functional theory to quantitatively predict quantum mechanical responses arising from strain gradients. The proposed framework establishes a direct connection between electronic structure and higher-order continuum mechanics, enabling the evaluation of non-local electromechanical couplings directly from first principles. In particular, the theory provides a fundamental description of how strain gradients perturb the electronic ground state, modify polarization fields, and generate higher-order stress measures beyond the conventional Cauchy stress tensor. The higher-order quantum stress theory developed here offers a convenient and predictive tool for analysing intrinsic size effects in condensed matter systems and nanostructured materials. To demonstrate the capability and robustness of the proposed framework, we apply it to investigate quantum flexoelectricity in a variety of dielectric materials, including ferroelectric crystals. The flexoelectric coefficients predicted from the present theory show good agreement with available experimental measurements and previously reported computational studies. These results highlight the potential of the higher-order quantum stress framework as a powerful approach for studying nanoscale electromechanical phenomena and designing advanced functional materials with enhanced flexoelectric and strain gradient-driven properties.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Higher-order quantum stress and quantum flexoelectricity

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年6月15日

查看全文
  • Jun Li,
  • Shaofan Li

摘要

Strain gradients can significantly redistribute electron charge density, thereby inducing net dipole moments and generating higher-order electromechanical interactions in materials. These effects give rise to the novel concepts of higher-order quantum stress and quantum couple stress, which have not yet been systematically explored within a rigorous quantum mechanical framework. Understanding such higher-order phenomena is particularly important at nanometer and sub-micron length scales, where strain gradient effects become increasingly pronounced and classical continuum theories often lose predictive capability. In this work, we develop a rigorous theory of higher-order quantum stress within the framework of density functional theory to quantitatively predict quantum mechanical responses arising from strain gradients. The proposed framework establishes a direct connection between electronic structure and higher-order continuum mechanics, enabling the evaluation of non-local electromechanical couplings directly from first principles. In particular, the theory provides a fundamental description of how strain gradients perturb the electronic ground state, modify polarization fields, and generate higher-order stress measures beyond the conventional Cauchy stress tensor. The higher-order quantum stress theory developed here offers a convenient and predictive tool for analysing intrinsic size effects in condensed matter systems and nanostructured materials. To demonstrate the capability and robustness of the proposed framework, we apply it to investigate quantum flexoelectricity in a variety of dielectric materials, including ferroelectric crystals. The flexoelectric coefficients predicted from the present theory show good agreement with available experimental measurements and previously reported computational studies. These results highlight the potential of the higher-order quantum stress framework as a powerful approach for studying nanoscale electromechanical phenomena and designing advanced functional materials with enhanced flexoelectric and strain gradient-driven properties.