Observation of Giant Spin-orbit Interaction in Graphene and Heavy Metal Heterostructures

Overview

Journal RSC Adv

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2022 May 9

PMID 35527934

Authors

Amir Muhammad Afzal

Kuen Hong Min

Byung Min Ko

Jonghwa Eom

Affiliations

Soon will be listed here.

Abstract

Graphene is a promising material demonstrating some interesting phenomena such as the spin Hall effect, bipolar transistor effect, and non-trivial topological states. However, graphene has an intrinsically small spin-orbit interaction (SOI), making it difficult to apply in spintronic devices. The electronic band structure of graphene makes it possible to develop a systematic method to enhance SOI extrinsically. In this study, we designed a graphene field-effect transistor with a Pb layer intercalated between graphene (Gr) and Au layers and studied the effect on the strength of the SOI. The SOI in our system was significantly increased to 80 meV, which led to a giant non-local signal (∼180 Ω) at room temperature due to the spin Hall effect. Further, we extract key parameters of spin transport from the length and width dependence of non-local measurement. To support these findings, we also measured the temperature and gate-dependent weak localization (WL) effect. We obtained the magnitude of the SOI and spin relaxation time of Gr quantitative analysis of WL. The SOI magnitudes estimated from the non-local signal and the WL effect are close in value. The enhancement of the SOI of Gr at room temperature is a potential simple manipulation method to explore the use of this material for spin-based applications.

References

Wolf S, Awschalom D, Buhrman R, Daughton J, von Molnar S, Roukes M . Spintronics: a spin-based electronics vision for the future. Science. 2001; 294(5546):1488-95. DOI: 10.1126/science.1065389. View

Ochoa H, Neto A, Guinea F . Elliot-Yafet mechanism in graphene. Phys Rev Lett. 2012; 108(20):206808. DOI: 10.1103/PhysRevLett.108.206808. View

Tikhonenko F, Horsell D, Gorbachev R, Savchenko A . Weak localization in graphene flakes. Phys Rev Lett. 2008; 100(5):056802. DOI: 10.1103/PhysRevLett.100.056802. View

Kamalakar M, Groenveld C, Dankert A, Dash S . Long distance spin communication in chemical vapour deposited graphene. Nat Commun. 2015; 6:6766. PMC: 4433146. DOI: 10.1038/ncomms7766. View

Schedin F, Geim A, Morozov S, Hill E, Blake P, Katsnelson M . Detection of individual gas molecules adsorbed on graphene. Nat Mater. 2007; 6(9):652-5. DOI: 10.1038/nmat1967. View

Ferrari A, Meyer J, Scardaci V, Casiraghi C, Lazzeri M, Mauri F . Raman spectrum of graphene and graphene layers. Phys Rev Lett. 2006; 97(18):187401. DOI: 10.1103/PhysRevLett.97.187401. View

Graf D, Molitor F, Ensslin K, Stampfer C, Jungen A, Hierold C . Spatially resolved Raman spectroscopy of single- and few-layer graphene. Nano Lett. 2007; 7(2):238-42. DOI: 10.1021/nl061702a. View

Afzal A, Khan M, Nazir G, Dastgeer G, Aftab S, Akhtar I . Gate Modulation of the Spin-orbit Interaction in Bilayer Graphene Encapsulated by WS films. Sci Rep. 2018; 8(1):3412. PMC: 5821884. DOI: 10.1038/s41598-018-21787-y. View

Blugel . Two-dimensional ferromagnetism of 3d, 4d, and 5d transition metal monolayers on noble metal (001) substrates. Phys Rev Lett. 1992; 68(6):851-854. DOI: 10.1103/PhysRevLett.68.851. View

10.

Novoselov K, Geim A, Morozov S, Jiang D, Zhang Y, Dubonos S . Electric field effect in atomically thin carbon films. Science. 2004; 306(5696):666-9. DOI: 10.1126/science.1102896. View

11.

Balakrishnan J, Koon G, Avsar A, Ho Y, Lee J, Jaiswal M . Giant spin Hall effect in graphene grown by chemical vapour deposition. Nat Commun. 2014; 5:4748. DOI: 10.1038/ncomms5748. View

12.

Avsar A, Tan J, Taychatanapat T, Balakrishnan J, Koon G, Yeo Y . Spin-orbit proximity effect in graphene. Nat Commun. 2014; 5:4875. DOI: 10.1038/ncomms5875. View

13.

Tombros N, Jozsa C, Popinciuc M, Jonkman H, Wees B . Electronic spin transport and spin precession in single graphene layers at room temperature. Nature. 2007; 448(7153):571-4. DOI: 10.1038/nature06037. View

14.

Mihajlovic G, Pearson J, Garcia M, Bader S, Hoffmann A . Negative nonlocal resistance in mesoscopic gold Hall bars: absence of the giant spin Hall effect. Phys Rev Lett. 2009; 103(16):166601. DOI: 10.1103/PhysRevLett.103.166601. View

15.

Wang Z, Ki D, Chen H, Berger H, MacDonald A, Morpurgo A . Strong interface-induced spin-orbit interaction in graphene on WS2. Nat Commun. 2015; 6:8339. PMC: 4595714. DOI: 10.1038/ncomms9339. View

16.

McCann E, Falko V . z→-z symmetry of spin-orbit coupling and weak localization in graphene. Phys Rev Lett. 2012; 108(16):166606. DOI: 10.1103/PhysRevLett.108.166606. View

17.

Abanin D, Gorbachev R, Novoselov K, Geim A, Levitov L . Giant spin-Hall effect induced by the Zeeman interaction in graphene. Phys Rev Lett. 2011; 107(9):096601. DOI: 10.1103/PhysRevLett.107.096601. View

18.

Lara-Avila S, Tzalenchuk A, Kubatkin S, Yakimova R, Janssen T, Cedergren K . Disordered Fermi liquid in epitaxial graphene from quantum transport measurements. Phys Rev Lett. 2011; 107(16):166602. DOI: 10.1103/PhysRevLett.107.166602. View

19.

Neto A, Guinea F . Impurity-induced spin-orbit coupling in graphene. Phys Rev Lett. 2009; 103(2):026804. DOI: 10.1103/PhysRevLett.103.026804. View

20.

Han W, Kawakami R, Gmitra M, Fabian J . Graphene spintronics. Nat Nanotechnol. 2014; 9(10):794-807. DOI: 10.1038/nnano.2014.214. View