Spin to charge conversion in MoS$_{2}$ monolayer with spin pumping

Layered transition-metal dichalcogenides (TMDs) family are gaining increasing importance due to their unique electronic band structures, promising interplay among light, valley (pseudospin), charge and spin degrees of freedom. They possess large intrinsic spin-orbit interaction which make them most relevant for the emerging field of spin-orbitronics. Here we report on the conversion of spin current to charge current in MoS2 monolayer. Using spin pumping from a ferromagnetic layer (10 nm of cobalt) we find that the spin to charge conversion is highly efficient. Analysis in the frame of the inverse Rashba-Edelstein (RE) effect yields a RE length in excess of 4 nm at room temperature. Furthermore, owing to the semiconducting nature of MoS$_{2}$, it is found that back-gating allows electrical field control of the spin-relaxation rate of the MoS$_{2}$-metallic stack.

[1]  D. Ralph,et al.  Spin transfer torque devices utilizing the giant spin Hall effect of tungsten , 2012, 1208.1711.

[2]  E. Rashba.  Theory of electrical spin injection: Tunnel contacts as a solution of the conductivity mismatch problem , 2000, cond-mat/0010473.

[3]  Albert Fert,et al.  Conditions for efficient spin injection from a ferromagnetic metal into a semiconductor , 2001 .

[4]  T Trypiniotis,et al.  Electrically tunable spin injector free from the impedance mismatch problem. , 2011, Nature materials.

[5]  J. Appenzeller,et al.  High performance multilayer MoS2 transistors with scandium contacts. , 2013, Nano letters.

[6]  Wang Yao,et al.  Valley polarization in MoS2 monolayers by optical pumping. , 2012, Nature nanotechnology.

[7]  M. Kamalakar,et al.  High-performance molybdenum disulfide field-effect transistors with spin tunnel contacts. , 2014, ACS nano.

[8]  F. Guinea,et al.  Spin memory and spin-lattice relaxation in two-dimensional hexagonal crystals , 2013, 1308.0928.

[9]  Yugui Yao,et al.  Intrinsic spin Hall effect in monolayers of group-VI dichalcogenides: A first-principles study , 2012, 1209.1964.

[10]  F. Freimuth,et al.  Symmetry and magnitude of spin-orbit torques in ferromagnetic heterostructures. , 2013, Nature nanotechnology.

[11]  J. Pearson,et al.  Research Update: Spin transfer torques in permalloy on monolayer MoS2 , 2016 .

[12]  Yoichi Ando,et al.  Spin-electricity conversion induced by spin injection into topological insulators. , 2014, Physical review letters.

[13]  S. Rezende,et al.  Spin-Current to Charge-Current Conversion and Magnetoresistance in a Hybrid Structure of Graphene and Yttrium Iron Garnet. , 2015, Physical review letters.

[14]  Lei Liu,et al.  Electric control of spin in monolayer WSe2 field effect transistors , 2013, Nanotechnology.

[15]  Luis Morellón,et al.  Control of the spin to charge conversion using the inverse Rashba-Edelstein effect , 2015 .

[16]  H. Jaffrès,et al.  Spin pumping and inverse spin Hall effect in platinum: the essential role of spin-memory loss at metallic interfaces. , 2013, Physical review letters.

[17]  Wang Yao,et al.  Spin and pseudospins in layered transition metal dichalcogenides , 2014, Nature Physics.

[18]  A. Brataas,et al.  Spin pumping and magnetization dynamics in metallic multilayers , 2002, cond-mat/0208091.

[19]  J. Robinson,et al.  Electrical detection of charge-current-induced spin polarization due to spin-momentum locking in Bi2Se3. , 2014, Nature nanotechnology.

[20]  A. Manchon.  A new moment for Berry , 2014, Nature Physics.

[21]  Ji Feng,et al.  Valley-selective circular dichroism of monolayer molybdenum disulphide , 2012, Nature Communications.

[22]  A. Fert,et al.  Spin-to-charge conversion using Rashba coupling at the interface between non-magnetic materials , 2013, Nature Communications.

[23]  Yingchun Cheng,et al.  Giant spin-orbit-induced spin splitting in two-dimensional transition-metal dichalcogenide semiconductors , 2011 .

[24]  A. Neto,et al.  Giant spin Hall effect in graphene grown by chemical vapour deposition , 2014, Nature Communications.

[25]  J. Hirsch.  Spin Hall Effect , 1999, cond-mat/9906160.

[26]  J. Pflaum,et al.  Gilbert damping and g-factor in FexCo1−x alloy films , 1995 .

[27]  M. Harder,et al.  Analysis of the line shape of electrically detected ferromagnetic resonance , 2011, 1105.3236.

[28]  G. Woltersdorf,et al.  Inverse spin Hall effect inNi81Fe19/normal-metal bilayers , 2013, 1307.2947.

[29]  Kevin Garello,et al.  Spin-orbit torque magnetization switching of a three-terminal perpendicular magnetic tunnel junction , 2013, 1310.8235.

[30]  P. L. McEuen,et al.  The valley Hall effect in MoS2 transistors , 2014, Science.

[31]  J. S. Lee,et al.  Spin-transfer torque generated by a topological insulator , 2014, Nature.

[32]  S. Parkin,et al.  Role of transparency of platinum–ferromagnet interfaces in determining the intrinsic magnitude of the spin Hall effect , 2015, 1504.07929.

[33]  Spin-orbit proximity effect in graphene. , 2014, Nature communications.

[34]  Keliang He,et al.  Control of valley polarization in monolayer MoS2 by optical helicity. , 2012, Nature nanotechnology.

[35]  H. Wen,et al.  Control of Schottky barriers in single layer MoS2 transistors with ferromagnetic contacts. , 2013, Nano letters.