Spin-gapless semiconducting Cl-intercalated phosphorene bilayer: a perfect candidate material to identify its ferroelectric states by spin-Seebeck currents

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Vol. 1; no. 8; pp. 3188 - 3195
• Main Authors: Wu, Dan-Dan, Ji, Yu-Tian, Du, Gui-Fang, Yue, Xiao-Yu, Wang, Yi-Yan, Li, Qiu-Ju, Sun, Xue-Feng, Fu, Hua-Hua
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 24.02.2022
• Subjects: Adatoms; Bilayers; Chlorine; Electric fields; Electric polarization; Energy dissipation; Ferroelectric materials; Ferroelectricity; Ferromagnetic materials; Interdisciplinary subjects; Materials science; Materials selection; Multiferroic materials; Phosphorene; Plane strain; Seebeck effect; Spintronics; Vertical polarization
• DOI: 10.1039/d1tc05932g
• ISSN: 2050-7526

Two-dimensional multiferroic materials, combining the ferroelectric (FE) state with the ferromagnetic (FM) state, have long been regarded as one of the core topics in materials science. However, realizing a low-energy-dissipation approach to read the FE states is still a hard task. Here, we propose a bilayer phosphorene halogenated by chlorine (Cl) adatoms to induce the layer-dependent single-atom FE states with vertical electric polarization and construct the related spin caloritronic devices. Our theoretical studies uncover several interesting findings: (i) the halogenated monolayer phosphorene produces single-atom FE states and two nearly symmetrical spin-splitting states around the Fermi level, providing two spin-dependent transport channels for the generation of a well-defined spin-Seebeck effect (SSE); (ii) a pure thermal spin current can be obtained by adjusting the Cl-adatom concentration or by using an in-plane strain engineering technique; (iii) the spin-Seebeck current is tightly associated with the layer-dependent FE state, and they both can be switched simultaneously to the other layer by an external electric field. Our theoretical results not only propose a low-energy-dissipation approach to realize the readout of single-atom FE states, but also develop further the new interdisciplinary subject, i.e. , the spin-ferroelectro-caloritronics. Two-dimensional multiferroic materials, combining the ferroelectric (FE) state with the ferromagnetic (FM) state, have long been regarded as one of the core topics in materials science.