Abstract
Two-dimensional materials offer new opportunities for both fundamental science and technological applications, by exploiting the electron’s spin. Although graphene is very promising for spin communication due to its extraordinary electron mobility, the lack of a bandgap restricts its prospects for semiconducting spin devices such as spin diodes and bipolar spin transistors. The recent emergence of two-dimensional semiconductors could help overcome this basic challenge. In this letter we report an important step towards making two-dimensional semiconductor spin devices. We have fabricated a spin valve based on ultrathin (∼5 nm) semiconducting black phosphorus (bP), and established fundamental spin properties of this spin channel material, which supports all electrical spin injection, transport, precession and detection up to room temperature. In the non-local spin valve geometry we measure Hanle spin precession and observe spin relaxation times as high as 4 ns, with spin relaxation lengths exceeding 6 μm. Our experimental results are in a very good agreement with first-principles calculations and demonstrate that the Elliott–Yafet spin relaxation mechanism is dominant. We also show that spin transport in ultrathin bP depends strongly on the charge carrier concentration, and can be manipulated by the electric field effect.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Han, W., Kawakami, R. K., Gmitra, M. & Fabian, J. Graphene spintronics. Nat. Nanotech. 9, 794–807 (2014).
Zutic, I., Fabian, J. & Erwin, S. C. Bipolar spintronics: fundamentals and applications. IBM J. Res. Dev. 50, 121–139 (2006).
Wolf, S. A. et al. Spintronics: a spin-based electronics vision for the future. Science 294, 1488–1495 (2001).
Jansen, R. Silicon spintronics. Nat. Mater. 11, 400–408 (2012).
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).
Appelbaum, I., Huang, B. & Monsma, D. J. Electronic measurement and control of spin transport in silicon. Nature 447, 295–298 (2007).
Novoselov, K. S. et al. Electric field effect in atomically thin carbon films. Science 306, 666–669 (2004).
Tombros, N., Jozsa, C., Popinciuc, M., Jonkman, H. T. & van Wees, B. J. Electronic spin transport and spin precession in single graphene layers at room temperature. Nature 448, 571–574 (2007).
Drögeler, M. et al. Spin lifetimes exceeding 12 ns in graphene nonlocal spin valve devices. Nano Lett. 16, 3533–3539 (2016).
Radisavljevic, B., Radenovic, A., Brivio, J., Giacometti, V. & Kis, A. Single-layer MoS2 transistors. Nat. Nanotech. 6, 147–150 (2011).
Li, L. et al. Black phosphorus field-effect transistors. Nat. Nanotech. 9, 372–377 (2014).
Yang, L. et al. Long-lived nanosecond spin relaxation and spin coherence of electrons in monolayer MoS2 and WS2 . Nat. Phys. 11, 830–834 (2015).
Katmis, F. et al. A high-temperature ferromagnetic topological insulating phase by proximity coupling. Nature 533, 513–516 (2016).
Hsu, W.-T. et al. Optically initialized robust valley-polarized holes in monolayer WSe2 . Nat. Commun. 6, 8963 (2015).
Liu, H. et al. Phosphorene: an unexplored 2D semiconductor with a high hole mobility. ACS Nano 8, 4033–4041 (2014).
Long, G. et al. Achieving ultrahigh carrier mobility in two-dimensional hole gas of black phosphorus. Nano Lett. 16, 7768–7773 (2016).
Popović, Z. S., Kurdestany, J. M. & Satpathy, S. Electronic structure and anisotropic Rashba spin–orbit coupling in monolayer black phosphorus. Phys. Rev. B 92, 35135 (2015).
Li, P. & Appelbaum, I. Electrons and holes in phosphorene. Phys. Rev. B 90, 115439 (2014).
Kurpas, M., Gmitra, M. & Fabian, J. Spin–orbit coupling and spin relaxation in phosphorene: intrinsic versus extrinsic effects. Phys. Rev. B 94, 155423 (2016).
Avsar, A. et al. Air-stable transport in graphene-contacted, fully encapsulated ultrathin black phosphorus-based field-effect transistors. ACS Nano 9, 4138–4145 (2015).
Avsar, A. et al. Electronic spin transport in dual-gated bilayer graphene. NPG Asia Mater. 8, e274 (2016).
Kochan, D., Gmitra, M. & Fabian, J. Spin relaxation mechanism in graphene: resonant scattering by magnetic impurities. Phys. Rev. Lett. 112, 116602 (2014).
Yamaguchi, T. et al. Electrical spin injection into graphene through monolayer hexagonal boron nitride. Appl. Phys. Express 6, 73001 (2013).
Ribeiro, H. B. et al. Unusual angular dependence of the Raman response in black phosphorus. ACS Nano 9, 4270–4276 (2015).
Jönsson-Åkerman, B. J. et al. Reliability of normal-state current–voltage characteristics as an indicator of tunnel-junction barrier quality. Appl. Phys. Lett. 77, 1870 (2000).
Farmanbar, M. & Brocks, G. Controlling the Schottky barrier at MoS2/metal contacts by inserting a BN monolayer. Phys. Rev. B 91, 161304 (2015).
Cai, Y., Zhang, G. & Zhang, Y.-W. Electronic properties of phosphorene/graphene and phosphorene/hexagonal boron nitride heterostructures. J. Phys. Chem. C 119, 13929–13936 (2015).
Jedema, F. J., Filip, A. T. & van Wees, B. J. Electrical spin injection and accumulation at room temperature in an all-metal mesoscopic spin valve. Nature 410, 345–348 (2001).
Fukuma, Y. et al. Giant enhancement of spin accumulation and long-distance spin precession in metallic lateral spin valves. Nat. Mater. 10, 527–531 (2011).
Sasaki, T. et al. Evidence of electrical spin injection into silicon using MgO tunnel barrier. IEEE Trans. Magn. 46, 1436–1439 (2010).
Han, W. et al. Tunneling spin injection into single layer graphene. Phys. Rev. Lett. 105, 167202 (2010).
Takahashi, S. & Maekawa, S. Spin injection and detection in magnetic nanostructures. Phys. Rev. B 67, 52409 (2003).
Johnson, M. & Silsbee, R. H. Interfacial charge-spin coupling: injection and detection of spin magnetization in metals. Phys. Rev. Lett. 55, 1790–1793 (1985).
Elliott, R. J. Theory of the effect of spin–orbit coupling on magnetic resonance in some semiconductors. Phys. Rev. 96, 266–279 (1954).
Yafet, Y. Solid State Phys. Ed. by F. Seitz D. Turnbull Vol. 14 (Academic, 1963).
Fabian, J. & Das Sarma, S. Spin relaxation of conduction electrons in polyvalent metals: theory and a realistic calculation. Phys. Rev. Lett. 81, 5624–5627 (1998).
Zimmermann, B. et al. Anisotropy of spin relaxation in metals. Phys. Rev. Lett. 109, 236603 (2012).
Lou, X. et al. Electrical detection of spin transport in lateral ferromagnet–semiconductor devices. Nat. Phys. 3, 197–202 (2007).
Suzuki, T. et al. Room-temperature electron spin transport in a highly doped Si channel. Appl. Phys. Express 4, 23003 (2011).
Peterson, T. A. et al. Spin injection and detection up to room temperature in Heusler ∼alloy/n-GaAs spin valves. Phys. Rev. B 94, 235309 (2016).
Miyakawa, T. et al. Efficient gate control of spin-valve signals and Hanle signals in GaAs channel with p–i–n junction-type back-gate structure. Appl. Phys. Express 9, 23103 (2016).
Tahara, T. et al. Observation of large spin accumulation voltages in nondegenerate Si spin devices due to spin drift effect: experiments and theory. Phys. Rev. B 93, 214406 (2016).
Tahara, T. et al. Room-temperature operation of Si spin MOSFET with high on/off spin signal ratio. Appl. Phys. Express 8, 113004 (2015).
Weeks, C., Hu, J., Alicea, J., Franz, M. & Wu, R. Engineering a robust quantum spin Hall state in graphene via adatom deposition. Phys. Rev. X 1, 21001 (2011).
Cui, X. et al. Multi-terminal transport measurements of MoS2 using a van der Waals heterostructure device platform. Nat. Nanotech. 10, 534–540 (2015).
Taniguchi, T. & Watanabe, K. Synthesis of high-purity boron nitride single crystals under high pressure by using Ba–BN solvent. J. Cryst. Growth 303, 525–529 (2007).
Brown, A. & Rundqvist, S. Refinement of the crystal structure of black phosphorus. Acta Crystallogr. 19, 684–685 (1965).
Giannozzi, P. et al. QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials. J. Phys. Condens. Matter 21, 395502 (2009).
Perdew, J. P. et al. Restoring the density-gradient expansion for exchange in solids and surfaces. Phys. Rev. Lett. 100, 136406 (2008).
Blaha, P., Schwarz, K., Madsen, G. K. H., Kvasnicka, D. & Luitz, J. WIEN2K, An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal Properties (Karlheinz Schwarz. Techn. Univ. Wien, Aust., 2016).
Tran, F. & Blaha, P. Accurate band gaps of semiconductors and insulators with a semilocal exchange-correlation potential. Phys. Rev. Lett. 102, 226401 (2009).
Li, L. et al. Quantum oscillations in a two-dimensional electron gas in black phosphorus thin films. Nat. Nanotech. 10, 608–613 (2015).
Chen, X. High-quality sandwiched black phosphorus heterostructures and its quantum oscillations. Nat. Commun. 6, 7315 (2015).
Acknowledgements
We thank S. Natarajan and Y. Yeo for their help. B.Ö. would like to acknowledge support by the National Research Foundation, Prime Minister’s Office, Singapore, under its Medium Sized Centre Programme and CRP award ‘Novel 2D materials with tailored properties: beyond graphene’ (Grant number R-144-000-295-281) and Competitive Research Programme (CRP Award No. NRF-CRP9-2011-3). M.K. acknowledges support from the DFG SPP 1538 and National Science Centre (NCN) grant DEC-2013/11/B/ST3/00824. M.G. and J.F. acknowledge support from DFG SFB 689 and GRK 1570. J.F. acknowledges support by the European Union’s Horizon 2020 research and innovation programme under Grant agreement No. 696656. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan and JSPS KAKENHI Grant Numbers JP26248061, JP15K21722 and JP25106006.
Author information
Authors and Affiliations
Contributions
B.Ö. initiated and coordinated the work. A.A. and B.Ö. designed the experiments. A.A. and J.Y.T. fabricated the samples. A.A. performed transport measurements. K.W. and T.T. grew the hBN and bP crystals. M.K., M.G. and J.F. provided the theoretical work. All authors discussed the results and wrote the manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary information
Supplementary information (PDF 601 kb)
Rights and permissions
About this article
Cite this article
Avsar, A., Tan, J., Kurpas, M. et al. Gate-tunable black phosphorus spin valve with nanosecond spin lifetimes. Nature Phys 13, 888–893 (2017). https://doi.org/10.1038/nphys4141
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nphys4141
This article is cited by
-
Highly anisotropic spin transport in ultrathin black phosphorus
Nature Materials (2024)
-
Substrate effects on spin relaxation in two-dimensional Dirac materials with strong spin-orbit coupling
npj Computational Materials (2023)
-
Ballistic transport spectroscopy of spin-orbit-coupled bands in monolayer graphene on WSe2
Nature Communications (2023)
-
Photogalvanic effect induced charge and spin photocurrent in group-V monolayer systems
Frontiers of Physics (2023)
-
Spin–orbit coupling in buckled monolayer nitrogene
Scientific Reports (2022)