Spin injection and helicity control of surface spin photocurrent in a three dimensional topological insulator

A three-dimensional (3D) topological insulator (TI) is a unique quantum phase of matter with exotic physical properties and promising spintronic applications. However, surface spin current in a common 3D TI remains difficult to control and the out-of-plane spin texture is largely unexplored. Here, by means of surface spin photocurrent in Bi2Te3 TI devices driven by circular polarized light, we identify the subtle effect of the spin texture of the topological surface state including the hexagonal warping term on the surface current. By exploring the out-of-plane spin texture, we demonstrate spin injection from GaAs to TI and its significant contribution to the surface current, which can be manipulated by an external magnetic field. These discoveries pave the way to not only intriguing new physics but also enriched spin functionalities by integrating TI with conventional semiconductors, such that spin-enabled optoelectronic devices may be fabricated in such hybrid structures.

[1]  P. Tan,et al.  Temperature and electron density dependence of spin relaxation in GaAs/AlGaAs quantum well , 2010, Nanoscale research letters.

[2]  P. Hosur,et al.  Circular photogalvanic effect on topological insulator surfaces: Berry-curvature-dependent response , 2011 .

[3]  Matthew Brahlek,et al.  Observation of inverse spin hall effect in bismuth selenide , 2014 .

[4]  S. Louie,et al.  Spin polarization of photoelectrons from topological insulators. , 2012, Physical review letters.

[5]  Muñoz,et al.  Spin relaxation in intrinsic GaAs quantum wells: Influence of excitonic localization. , 1995, Physical review. B, Condensed matter.

[6]  N. Gedik,et al.  Observation of a warped helical spin texture in Bi2Se3 from circular dichroism angle-resolved photoemission spectroscopy. , 2011, Physical review letters.

[7]  Stuart A. Wolf,et al.  Spintronics : A Spin-Based Electronics Vision for the Future , 2009 .

[8]  Dmytro Pesin,et al.  Spintronics and pseudospintronics in graphene and topological insulators. , 2012, Nature materials.

[9]  S. Louie,et al.  Photoelectron spin-flipping and texture manipulation in a topological insulator , 2013, Nature Physics.

[10]  Kang L. Wang,et al.  Magnetization switching through giant spin-orbit torque in a magnetically doped topological insulator heterostructure. , 2014, Nature materials.

[11]  K. W. Kim,et al.  Tunable photogalvanic effect on topological insulator surfaces via proximity interactions , 2012, 1208.2619.

[12]  S. Sikdar,et al.  Fundamentals and applications , 1998 .

[13]  D. Hsieh,et al.  A topological Dirac insulator in a quantum spin Hall phase , 2008, Nature.

[14]  A. Holleitner,et al.  Ultrafast helicity control of surface currents in topological insulators with near-unity fidelity , 2015, Nature Communications.

[15]  Hongtao Yuan,et al.  Generation and electric control of spin-valley-coupled circular photogalvanic current in WSe2. , 2014, Nature Nanotechnology.

[16]  M. Kriener,et al.  Direct measurement of the out-of-plane spin texture in the Dirac-cone surface state of a topological insulator. , 2011, Physical review letters.

[17]  Xi Dai,et al.  Topological insulators in Bi2Se3, Bi2Te3 and Sb2Te3 with a single Dirac cone on the surface , 2009 .

[18]  S. Sarma,et al.  Spintronics: Fundamentals and applications , 2004, cond-mat/0405528.

[19]  R. Cava,et al.  Observation of a large-gap topological-insulator class with a single Dirac cone on the surface , 2009 .

[20]  Sergey Ganichev,et al.  Spin photocurrents in quantum wells , 2003 .

[21]  Z. K. Liu,et al.  Experimental Realization of a Three-Dimensional Topological Insulator , 2010 .

[22]  Dapeng Yu,et al.  Topological surface state enhanced photothermoelectric effect in Bi2Se3 nanoribbons. , 2014, Nano letters.

[23]  S. Adachi,et al.  Exciton spin dynamics in GaAs quantum wells , 1997 .

[24]  I. Buyanova,et al.  The Hanle effect and electron spin polarization in InAs/GaAs quantum dots up to room temperature , 2012, Nanotechnology.

[25]  J. Jiang,et al.  Electron-spin relaxation in bulk III-V semiconductors from a fully microscopic kinetic spin Bloch equation approach , 2008, 0812.0862.

[26]  Q. Xue,et al.  Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator , 2013, Science.

[27]  D. Vanderbilt,et al.  Magnetoelectric polarizability and axion electrodynamics in crystalline insulators. , 2008, Physical review letters.

[28]  P. Jarillo-Herrero,et al.  Control over topological insulator photocurrents with light polarization. , 2011, Nature nanotechnology.

[29]  L. Fu,et al.  Superconducting proximity effect and majorana fermions at the surface of a topological insulator. , 2007, Physical review letters.

[30]  S. Artemenko,et al.  Photogalvanic effects in topological insulators , 2012, 1212.4983.