The exploration of ferroelectric phase transitions enables an in-depth understanding of ferroelectric switching and promising applications in information storage. However, controllably tuning the dynamics of ferroelectric phase transitions remains challenging owing to inaccessible hidden phases. Here, using protonic gating technology, we create a series of metastable ferroelectric phases and demonstrate their reversible transitions in layered ferroelectric α-In 2 Se 3 transistors. By varying the gate bias, protons can be incrementally injected or extracted, achieving controllable tuning of the ferroelectric α-In 2 Se 3 protonic dynamics across the channel and obtaining numerous intermediate phases. We unexpectedly discover that the gate tuning of α-In 2 Se 3 protonation is volatile and the created phases remain polar. Their origin, revealed by first-principles calculations, is related to the formation of metastable hydrogen-stabilized α-In 2 Se 3 phases. Furthermore, our approach enables ultralow gate voltage switching of different phases (below 0.4 volts). This work provides a possible avenue for accessing hidden phases in ferroelectric switching.

中文翻译：

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低工作电压下亚稳态铁电相的质子介导可逆切换

对铁电相变的探索使人们能够深入了解铁电开关和在信息存储中的有前途的应用。然而，由于难以接近的隐藏相，可控地调整铁电相变的动力学仍然具有挑战性。在这里，我们使用质子门控技术创建了一系列亚稳态铁电相，并展示了它们在层状铁电 α-In 中的可逆转变2个硒3个晶体管。通过改变栅极偏压，可以逐渐注入或提取质子，实现铁电 α-In 的可控调谐2个硒3个跨通道的质子动力学并获得许多中间相。我们意外地发现 α-In 的门控调谐2个硒3个质子化是不稳定的，所产生的相保持极性。第一性原理计算揭示了它们的起源与亚稳态氢稳定 α-In 的形成有关2个硒3个阶段。此外，我们的方法可实现不同相位的超低栅极电压切换（低于 0.4 伏）。这项工作为访问铁电开关中的隐藏相提供了可能的途径。