Much attention has been paid to the hidden Rashba effect exhibiting an intriguing spin-layer locking phenomenon observed in two-dimensional materials with inversion symmetry. This effect provides a new possibility for manipulating Rashba spin polarization even in centrosymmetric materials. We propose a mechanism exhibiting an unconventional hidden Rashba effect showing a unique helical spin texture in which two Fermi circles in different bands have the same spin helicity exhibiting a complete spin separation in space. We demonstrate such an unconventional hidden Rashba effect by showing the unique electronic structures of two-dimensional InTe with inversion symmetry investigated by the first-principles calculations. It is found that spins in both the inner and outer bands with the one helicity are located in the top sublayer whereas spins with the other helicity are in the bottom sublayer indicating a complete spatial spin separation. Strong spin-orbit coupling and a band inversion among two pairs of spin-degenerate bands are the main origins for the unconventional hidden Rashba involving two pairs of spin-degenerate bands rather than one pair, which gets usually involved in the conventional (hidden) Rashba effects. This new type of the hidden Rashba effect observed in two-dimensional InTe would broaden our understanding of the underlying physics of spin polarization phenomena eventually leading to a potential application in future spintronics.

人们对隐藏的拉什巴效应给予了很多关注，该效应表现出在具有反演对称性的二维材料中观察到的有趣的自旋层锁定现象。即使在中心对称材料中，这种效应也为操纵 Rashba 自旋极化提供了新的可能性。我们提出了一种表现出非常规隐藏拉什巴效应的机制，该效应表现出独特的螺旋自旋纹理，其中不同能带中的两个费米圆具有相同的自旋螺旋度，在空间中表现出完全的自旋分离。我们通过第一性原理计算研究了具有反演对称性的二维 InTe 的独特电子结构，证明了这种非常规的隐藏 Rashba 效应。研究发现，具有一种螺旋性的内带和外带中的自旋位于顶部子层，而具有另一种螺旋性的自旋位于底部子层，这表明完全的空间自旋分离。强自旋轨道耦合和两对自旋简并能带之间的能带反转是非常规隐藏 Rashba 的主要起源，涉及两对自旋简并能带而不是一对，这通常涉及常规（隐藏）Rashba影响。在二维 InTe 中观察到的这种新型隐藏 Rashba 效应将拓宽我们对自旋极化现象的基础物理的理解，最终在未来的自旋电子学中产生潜在的应用。强自旋轨道耦合和两对自旋简并能带之间的能带反转是非常规隐藏 Rashba 的主要起源，涉及两对自旋简并能带而不是一对，这通常涉及常规（隐藏）Rashba影响。在二维 InTe 中观察到的这种新型隐藏的 Rashba 效应将拓宽我们对自旋极化现象的基础物理的理解，最终导致其在未来自旋电子学中的潜在应用。强自旋轨道耦合和两对自旋简并能带之间的能带反转是非常规隐藏 Rashba 的主要起源，涉及两对自旋简并能带而不是一对，这通常涉及常规（隐藏）Rashba影响。在二维 InTe 中观察到的这种新型隐藏的 Rashba 效应将拓宽我们对自旋极化现象的基础物理的理解，最终导致其在未来自旋电子学中的潜在应用。