Abstract
Room-temperature magnetic semiconductors are crucial for next-generation spintronics, yet remain hindered by low Curie temperatures and volatile control mechanisms. Using density functional theory, we report Cr2NiSe4, a bipolar magnetic semiconductor (BMS) formed by Ni intercalation in bilayer CrSe2, with a Curie temperature of 495 K and a 0.40 eV band gap. We demonstrate nonvolatile control over carrier spin polarization in Al2Se3 heterostructures via ferroelectric switching: reversing the polarization of monolayer Al2Se3 induces a BMS-to-half-metal transition, whereas bilayer Al2Se3 enables half-metallic states with fully opposite spin polarization. This nonvolatile mechanism obviates the need for a continuous electric field and lowers energy consumption through interfacial charge transfer driven by ferroelectric band alignment. We propose a multiferroic memory device where ferroelectric polarization controls writing and spin-dependent conductance enables reading, enabling low-power, room-temperature operation. Our work establishes a feasible pathway for developing electrically tunable spintronics beyond the limits of Moore’s Law.
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References
Shalf, J. The future of computing beyond Moore’s law. Philos. Trans. R. Soc. Math. Phys. Eng. Sci. 378, 20190061 (2020).
Hu, J., Chen, L. & Nan, C. Multiferroic heterostructures integrating ferroelectric and magnetic materials. Adv. Mater. 28, 15–39 (2015).
Wang, J., Chen, A., Li, P. & Zhang, S. Magnetoelectric memory based on ferromagnetic/ferroelectric multiferroic heterostructure. Materials 14, 4623 (2021).
Dietl, T. A ten-year perspective on dilute magnetic semiconductors and oxides. Nat. Mater. 9, 965–974 (2010).
Ohno, H. A window on the future of spintronics. Nat. Mater. 9, 952–954 (2010).
Sato, K. et al. First-principles theory of dilute magnetic semiconductors. Rev. Mod. Phys. 82, 1633–1690 (2010).
Jungwirth, T., Sinova, J., Mašek, J., Kučera, J. & MacDonald, A. H. Theory of ferromagnetic (III, Mn)V semiconductors. Rev. Mod. Phys. 78, 809–864 (2006).
Dietl, T. & Ohno, H. Dilute ferromagnetic semiconductors: physics and spintronic structures. Rev. Mod. Phys. 86, 187–251 (2014).
Fiederling, R. et al. Injection and detection of a spin-polarized current in a light-emitting diode. Nature 402, 787–790 (1999).
Ohno, H. et al. Electric-field control of ferromagnetism. Nature 408, 944–946 (2000).
Mitra, C. et al. p-n diode with hole- and electron-doped lanthanum manganites. Appl. Phys. Lett. 79, 2408–2410 (2001).
Song, T. et al. Giant tunneling magnetoresistance in spin-filter van der Waals heterostructures. Science 360, 1214–1218 (2018).
Li, X. et al. Spin-dependent transport in van der Waals magnetic tunnel junctions with Fe3GeTe2 electrodes. Nano Lett. 19, 5133–5139 (2019).
Gorbenko, O. et al. Synthetic routes to colossal magnetoresistance manganites thin films containing unstable or highly volatile metal oxides. Thin Solid Films 515, 6395–6401 (2007).
Goel, S. et al. Room-temperature spin injection from a ferromagnetic semiconductor. Sci. Rep. 13, 2181 (2023).
Cinchetti, M. et al. Determination of spin injection and transport in a ferromagnet/organic semiconductor heterojunction by two-photon photoemission. Nat. Mater. 8, 115–119 (2008).
Huang, B. et al. Layer-dependent ferromagnetism in a van der Waals crystal down to the monolayer limit. Nature 546, 270–273 (2017).
Gong, C. et al. Discovery of intrinsic ferromagnetism in two-dimensional van der Waals crystals. Nature 546, 265–269 (2017).
Mermin, N. D. & Wagner, H. Absence of ferromagnetism or antiferromagnetism in one- or two-dimensional isotropic Heisenberg models. Phys. Rev. Lett. 17, 1307–1307 (1966).
Chu, J. et al. Sub-millimeter-scale growth of one-unit-cell-thick ferrimagnetic Cr2S3 nanosheets. Nano. Lett. 19, 2154–2161 (2019).
Cai, X. et al. Atomically thin CrCl3: an in-plane layered antiferromagnetic insulator. Nano. Lett. 19, 3993–3998 (2019).
Zhang, Z. et al. Direct photoluminescence probing of ferromagnetism in monolayer two-dimensional CrBr3. Nano. Lett. 19, 3138–3142 (2019).
Achinuq, B. et al. Covalent mixing in the 2D ferromagnet CrSiTe3 evidenced by magnetic X-Ray circular dichroism. Phys. Status Solidi 16, 2100566 (2021).
Lee, K. et al. Magnetic order and symmetry in the 2D semiconductor CrSBr. Nano. Lett. 21, 3511–3517 (2021).
Zhang, X. et al. Room-temperature intrinsic ferromagnetism in epitaxial CrTe2 ultrathin films. Nat. Commun. 12, 2492 (2021).
Xian, J.-J. et al. Spin mapping of intralayer antiferromagnetism and field-induced spin reorientation in monolayer CrTe2. Nat. Commun. 13, 257 (2022).
Wang, D. et al. Strain- and electron doping-induced in-plane spin orientation at room temperature in single-layer CrTe2. ACS Appl. Mater. Interfaces 16, 28791 (2024).
Chua, R. et al. Room temperature ferromagnetism of monolayer chromium telluride with perpendicular magnetic anisotropy. Adv. Mater. 33, 2103360 (2021).
Li, B. et al. Air-stable ultrathin Cr3Te4 nanosheets with thickness-dependent magnetic biskyrmions. Mater. Today 57, 66–74 (2022).
Zhang, Y. et al. Ultrathin magnetic 2D single-crystal CrSe. Adv. Mater. 31, 1900056 (2019).
Deng, Y. et al. Gate-tunable room-temperature ferromagnetism in two-dimensional Fe3GeTe2. Nature 563, 94–99 (2018).
Fei, Z. et al. Two-dimensional itinerant ferromagnetism in atomically thin Fe3GeTe2. Nat. Mater. 17, 778–782 (2018).
Seo, J. et al. Nearly room temperature ferromagnetism in a magnetic metal-rich van der Waals metal. Sci. Adv. 6, eaay8912 (2020).
Zhang, G. et al. Above-room-temperature strong intrinsic ferromagnetism in 2D van der Waals Fe3GaTe2 with large perpendicular magnetic anisotropy. Nat. Commun. 13, 5067 (2022).
Chen, Z., Yang, Y., Ying, T. & Guo, J.-G. High-Tc ferromagnetic semiconductor in thinned 3D Ising ferromagnetic metal Fe3GaTe2. Nano Lett. 24, 993–1000 (2024).
O’hara, D. et al. Room temperature intrinsic ferromagnetism in epitaxial manganese selenide films in the monolayer limit. Nano. Lett. 18, 3125–3131 (2018).
Xiao, H. et al. Van der Waals epitaxial growth of 2D layered room-temperature ferromagnetic CrS2. Adv. Mater. Interfaces 9, 2201353 (2022).
Yao, Y. et al. Synthesis of air-stable 1T-CrS2 thin films and their application in high-performance floating-gate memory. J. Mater. Chem. C. 12, 11513–11520 (2024).
Bonilla, M. et al. Strong room-temperature ferromagnetism in VSe2 monolayers on van der Waals substrates. Nat. Nanotechnol. 13, 289–293 (2018).
Meng, L. et al. Anomalous thickness dependence of Curie temperature in air-stable two-dimensional ferromagnetic 1T-CrTe2 grown by chemical vapor deposition. Nat. Commun. 12, 94–99 (2021).
Huang, C. et al. Ultra-high-temperature ferromagnetism in intrinsic tetrahedral semiconductors. JACS 141, 12413–12418 (2019).
Jiang, Z., Wang, P., Xing, J., Jiang, X. & Zhao, J. Screening and design of novel 2D ferromagnetic materials with high Curie temperature above room temperature. ACS Appl. Mater. Interfaces 10, 39032–39039 (2018).
Huang, C. et al. Toward intrinsic room-temperature ferromagnetism in two-dimensional semiconductors. JACS 140, 11519–11525 (2018).
Li, J.-W., Zhang, Z., You, J.-Y., Gu, B. & Su, G. Two-dimensional Heisenberg model with material-dependent superexchange interactions. Phys. Rev. B 107, 224411 (2023).
Li, J.-W., Su, G. & Gu, B. High temperature ferrimagnetic semiconductors by spin-dependent doping in high temperature antiferromagnets. npj Comput. Mater. 10, 205 (2024).
Li, J.-W., Su, G. & Gu, B. Possible room-temperature ferromagnetic semiconductor in monolayer MnSe2 through a metal-semiconductor transition. Phys. Rev. B 109, 134436 (2024).
Li, X., Li, J.-W., You, J.-Y., Su, G. & Gu, B. High curie temperature in diluted magnetic semiconductors (B, Mn) X (X = N, P, As, Sb). Phys. Rev. B 111, 184425 (2025).
Li, J.-W., Su, G. & Gu, B. Ferromagnetic semiconductor nanotubes with room Curie temperatures. npj Comput. Mater. 11, 292 (2025).
Jia-Wen Li, S. G. & Gu, B. Room-temperature ferromagnetism via superexchange in semiconductor (Cr4/6, Mo2/6)3Te6. Chin. Phys. Lett. 42, 090703 (2025).
Jiang, S., Li, L., Wang, Z., Mak, K. F. & Shan, J. Controlling magnetism in 2D CrI3 by electrostatic doping. Nat. Nanotechnol. 13, 549–553 (2018).
Zhao, F., Cao, T. & Louie, S. G. Topological phases in graphene nanoribbons tuned by electric fields. Phys. Rev. Lett. 127, 166401 (2021).
Hao, Q. et al. Phase identification and strong second harmonic generation in pure ϵ-InSe and its alloys. Nano Lett. 19, 2634–2640 (2019).
Fang, J. et al. Large unsaturated magnetoresistance of 2D magnetic semiconductor Fe-SnS2 homojunction. J. Semicond. 43, 092501 (2022).
Zhao, D. et al. Magnetic tuning in a novel half-metallic Ir2TeI2 monolayer. J. Semicond. 43, 052001 (2022).
Huang, S. et al. Strain-tunable van der Waals interactions in few-layer black phosphorus. Nat. Commun. 10, 94–99 (2019).
Li, Z. et al. Efficient strain modulation of 2D materials via polymer encapsulation. Nat. Commun. 11, 94–99 (2020).
Pathirage, V. et al. 2D materials by Design: Intercalation of Cr or Mn between two VSe2 van der Waals Layers. Nano Lett. 23, 9579–9586 (2023).
Zhou, J. et al. Layered intercalation materials. Adv. Mater. 33, 2004557 (2021).
Rajapakse, M. et al. Intercalation as a versatile tool for fabrication, property tuning, and phase transitions in 2d materials. npj 2D Mater. Appl. 5, 30 (2021).
Zhao, D. et al. Copper intercalation induces amorphization of 2D Cu/WO3 for room-temperature ferromagnetism. Angew. Chem. Int. Ed. 63, e202412811 (2024).
Zhou, J. et al. Heterodimensional superlattice with in-plane anomalous Hall effect. Nature 609, 46–51 (2022).
Peng, J. et al. Even-odd-layer-dependent ferromagnetism in 2D non-van-der-Waals CrCuSe2. Adv. Mater. 35, 2209365 (2023).
Zhang, J., Sun, J., Li, Y., Shi, F. & Cui, Y. Electrochemical control of copper intercalation into nanoscale Bi2Se3. Nano Lett. 17, 1741–1747 (2017).
Liu, X.-C. et al. Spontaneous self-intercalation of copper atoms into transition metal dichalcogenides. Sci. Adv. 6, eaay4092 (2020).
Wang, Z. et al. Room-temperature CrI3 magnets through lithiation. ACS Nano 18, 23058–23066 (2024).
Wang, Y. et al. Layer-number-independent two-dimensional ferromagnetism in Cr3Te4. Nano Lett. 22, 9964–9971 (2022).
Wen, Y. et al. Tunable room-temperature ferromagnetism in two-dimensional Cr2Te3. Nano Lett. 20, 3130–3139 (2020).
Chen, C. et al. Air-stable 2D Cr5Te8 nanosheets with thickness-tunable ferromagnetism. Adv. Mater. 34, 2107512 (2021).
Tang, B. et al. Phase engineering of Cr5Te8 with colossal anomalous Hall effect. Nat. Electron. 5, 224–232 (2022).
Liu, J. et al. Magnetic skyrmionic bubbles at room temperature and sign reversal of the topological Hall effect in a layered ferromagnet Cr0.87Te. ACS Nano 16, 13911–13918 (2022).
Tan, C. et al. Room-temperature magnetic phase transition in an electrically tuned van der Waals ferromagnet. Phys. Rev. Lett. 131, 166703 (2023).
Li, X., Wu, X., Li, Z., Yang, J. & Hou, J. G. Bipolar magnetic semiconductors: a new class of spintronics materials. Nanoscale 4, 5680 (2012).
Li, J., Li, X. & Yang, J. A review of bipolar magnetic semiconductors from theoretical aspects. Fundam. Res. 2, 511–521 (2022).
Ding, G., Hu, Y., Li, D., Wang, X. & Qin, D. Spin seebeck effect in bipolar magnetic semiconductor: a case of magnetic MoS2 nanotube. J. Adv. Res. 24, 391–396 (2020).
Jung, S. W. et al. Black phosphorus as a bipolar pseudospin semiconductor. Nat. Mater. 19, 277–281 (2020).
Li, X. & Yang, J. Bipolar magnetic materials for electrical manipulation of spin-polarization orientation. Phys. Chem. Chem. Phys. 15, 15793 (2013).
Guo, T. et al. Bipolar magnetic semiconductor and doping controllable spin transport property in 2D CoI2/MnBr2 heterostructure. Appl. Phys. Lett. 124, 062404 (2024).
Li, X. & Yang, J. Realizing two-dimensional magnetic semiconductors with enhanced curie temperature by antiaromatic ring based organometallic frameworks. JACS 141, 109–112 (2018).
Cheng, H. et al. Robust two-dimensional bipolar magnetic semiconductors by defect engineering. J. Mater. Chem. C. 6, 8435–8443 (2018).
Sheng, H. et al. Magnetic and phonon transport properties of two-dimensional room-temperature ferromagnet VSe2. J. Mater. Sci. 56, 15844–15858 (2021).
Liu, G. & Ke, S.-H. Electronic and transport engineering of A-type antiferromagnets with ferroelectric sandwich structure: Toward multistate nonvolatile memory applications. Nano Lett. 24, 10776–10782 (2024).
Lv, H., Niu, Y., Wu, X. & Yang, J. Electric-field tunable magnetism in van der Waals bilayers with A-type antiferromagnetic order: Unipolar versus bipolar magnetic semiconductor. Nano Lett. 21, 7050–7055 (2021).
Wang, Y. et al. Switchable half-metallicity in A-type antiferromagnetic NiI2 bilayer coupled with ferroelectric In2Se3. npj Comput. Mater. 8, 218 (2022).
Wang, H., Feng, Q., Li, X. & Yang, J. High-throughput computational screening for bipolar magnetic semiconductors. Research 2022, 9857631 (2022).
Li, Y. et al. Nonvolatile electrical control of spin polarization in the 2D bipolar magnetic semiconductor VSeF. npj Comput. Mater. 9, 50 (2023).
Zhang, L., Liu, Y., Wu, M. & Gao, G. Electric-field- and stacking-tuned antiferromagnetic FeClF bilayer: the coexistence of bipolar magnetic semiconductor and anomalous valley Hall effect. Adv. Funct. Mater. 35, 2417857 (2024).
Zhao, Y., Zhang, J., Yuan, S. & Chen, Z. Nonvolatile electrical control and heterointerface-induced half-metallicity of 2D ferromagnets. Adv. Funct. Mater. 29, 1901420 (2019).
Ding, W. et al. Prediction of intrinsic two-dimensional ferroelectrics in in2se3 and other III2-VI3 van der Waals materials. Nat. Commun. 8, 14956 (2017).
Yuan, Z. et al. Tuning electronic properties of 2D ferroelectric Al2Se3/graphene heterostructure by ferroelectric polarization and electric field. Phys. B 707, 417172 (2025).
Li, B. et al. Van der Waals epitaxial growth of air-stable CrSe2 nanosheets with thickness-tunable magnetic order. Nat. Mater. 20, 818–825 (2021).
Wu, L., Zhou, L., Zhou, X., Wang, C. & Ji, W. In-plane epitaxy-strain-tuning intralayer and interlayer magnetic coupling in CrSe2 and CrTe2 monolayers and bilayers. Phys. Rev. B 106, l081401 (2022).
Wang, C. et al. Bethe-slater-curve-like behavior and interlayer spin-exchange coupling mechanisms in two-dimensional magnetic bilayers. Phys. Rev. B 102, 020402 (2020).
Heyd, J., Scuseria, G. E. & Ernzerhof, M. Hybrid functionals based on a screened Coulomb potential. J. Chem. Phys. 118, 8207–8215 (2003).
Bravo, S., Orellana, P. A. & Rosales, L. Role of Coulomb interactions on the electronic properties of monolayer NiX2 (X=S, Se): A DFT+U+V study. Phys. Rev. B 108, 235138 (2023).
Garcia, V. et al. Ferroelectric control of spin polarization. Science 327, 1106–1110 (2010).
Kang, L. et al. Computational study on ferroelectric control over spin polarization in the bipolar magnetic semiconductor. Appl. Phys. Lett. 124, 132902 (2024).
Yang, T. H. et al. Ferroelectric transistors based on shear-transformation-mediated rhombohedral-stacked molybdenum disulfide. Nat. Electron. 7, 29–38 (2023).
Tao, L., Dou, M., Wang, X. & Tsymbal, E. Ferroelectric spin-orbit valve effect. Phys. Rev. Lett. 134, 076801 (2025).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Togo, A. & Tanaka, I. First principles phonon calculations in materials science. Scr. Mater. 108, 1–5 (2015).
Grimme, S. Semiempirical GGA-type density functional constructed with a long-range dispersion correction. J. Comput. Chem. 27, 1787–1799 (2006).
Acknowledgements
This work is supported by National Key R&D Program of China (Grant No. 2022YFA1405100), Chinese Academy of Sciences Project for Young Scientists in Basic Research (Grant No. YSBR-030), Basic Research Program of the Chinese Academy of Sciences Based on Major Scientific Infrastructures (Grant No. JZHKYPT-2021-08), and National Natural Science Foundation of China (Grant No. 12074378). G.S. was supported in part by the Innovation Program for Quantum Science and Technology under Grant No. 2024ZD0300500, NSFC No. 12447101 and the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB1270000).
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J.W.L. and B.G. conceived the original ideas and supervised the work. J.W.L. performed the first principles calculations and data analysis. G.S. joint the data discussions. All authors participated in discussing and editing the manuscripts.
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Li, JW., Su, G. & Gu, B. Nonvolatile ferroelectric switching of room-temperature bipolar magnetic semiconductors for energy-efficient spintronics. Commun Phys (2026). https://doi.org/10.1038/s42005-025-02485-4
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DOI: https://doi.org/10.1038/s42005-025-02485-4
