发表机构
Instituto Politécnico Nacional; Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Universitat Politècnica de Catalunya; Institució Catalana de Recerca i Estudis Avançats (ICREA)（国立理工学院; 巴塞罗那材料科学研究所（ICMAB-CSIC）; 加泰罗尼亚理工大学; 加泰罗尼亚研究与高等研究学院（ICREA））
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出利用带隙以上光激发降低纤锌矿铁电体翻转能垒的无场策略，以LaN为例验证了光诱导载流子降低能垒的机制，为低电压非易失存储开辟新路。
AI 中文摘要
纤锌矿铁电体兼具大的剩余极化和完全的CMOS兼容性，使其成为下一代非易失性存储器的领先平台。然而，其实际部署受到固有的大矫顽场的阻碍，该矫顽场源于分隔极性纤锌矿相与介导极化翻转的非极性六方相之间的高能垒。在此，我们利用第一性原理计算，提出了一种降低该能垒的替代性无场策略：带隙以上的电子光激发。以LaN作为代表性纤锌矿铁电体，我们展示了光诱导载流子显著降低了六方中间相与纤锌矿基态之间的能量差，从而急剧降低了铁电翻转的能垒。该效应源于极性相的光诱导部分金属化，它屏蔽了稳定铁电序的偶极-偶极相互作用，从而有利于竞争性的非极性结构。该机制的稳健性在岩盐多晶型中得到了进一步证实。我们的结果确立了光作为一种强大的、非侵入性的控制纤锌矿中铁电翻转的途径，为更快、更低电压和更节能的非易失性存储器技术开辟了道路。
英文摘要
Wurtzite ferroelectrics combine large remanent polarization with full CMOS compatibility, positioning them as a leading platform for next-generation non-volatile memory. Their practical deployment, however, is hindered by an intrinsically large coercive field, rooted in the high energy barrier separating the polar wurtzite phase from the nonpolar hexagonal phase that mediates polarization switching. Here, using first-principles calculations, we propose an alternative, field-free strategy for lowering this barrier: above-bandgap electronic photoexcitation. Taking LaN as a representative wurtzite ferroelectric, we show that light induced carriers dramatically reduce the energy difference between the hexagonal intermediate phase and the wurtzite ground state, sharply reducing the energy barrier to ferroelectric switching. This effect originates from a photoinduced partial metallization of the polar phase, which screens the dipole-dipole interactions that stabilize ferroelectric order and thereby favors the competing nonpolar structure. The robustness of this mechanism is further confirmed for the rocksalt polymorph. Our results establish light as a powerful, non-invasive route to controlling ferroelectric switching in wurtzites, opening a path toward faster, lower-voltage, and more energy-efficient non-volatile memory technologies.
Comments6 pages, 4 figures
