Generation, transport and detection of valley-locked spin photocurrent in WSe2–graphene–Bi2Se3 heterostructures

Soonyoung Cha, Minji Noh, Jehyun Kim, Jangyup Son, Hyemin Bae, Doeon Lee, Hoil Kim, Jekwan Lee, Ho Seung Shin, Sangwan Sim, Seunghoon Yang, Sooun Lee, Wooyoung Shim, Chul Ho Lee, Moon Ho Jo, Jun Sung Kim, Dohun Kim, Hyunyong Choi

Research output: Contribution to journalLetter

7 Citations (Scopus)

Abstract

Quantum optoelectronic devices capable of isolating a target degree of freedom (DoF) from other DoFs have allowed for new applications in modern information technology. Many works on solid-state spintronics have focused on methods to disentangle the spin DoF from the charge DoF1, yet many related issues remain unresolved. Although the recent advent of atomically thin transition metal dichalcogenides (TMDs) has enabled the use of valley pseudospin as an alternative DoF2,3, it is nontrivial to separate the spin DoF from the valley DoF since the time-reversal valley DoF is intrinsically locked with the spin DoF4. Here, we demonstrate lateral TMD–graphene–topological insulator hetero-devices with the possibility of such a DoF-selective measurement. We generate the valley-locked spin DoF via a circular photogalvanic effect in an electric-double-layer WSe2 transistor. The valley-locked spin photocarriers then diffuse in a submicrometre-long graphene layer, and the spin DoF is measured separately in the topological insulator via non-local electrical detection using the characteristic spin–momentum locking. Operating at room temperature, our integrated devices exhibit a non-local spin polarization degree of higher than 0.5, providing the potential for coupled opto-spin–valleytronic applications that independently exploit the valley and spin DoFs.

Original languageEnglish
Pages (from-to)910-914
Number of pages5
JournalNature Nanotechnology
Volume13
Issue number10
DOIs
Publication statusPublished - 2018 Oct 1

Fingerprint

Photocurrents
valleys
photocurrents
Heterojunctions
degrees of freedom
Magnetoelectronics
Spin polarization
Graphite
Optoelectronic devices
Graphene
Transition metals
Information technology
Transistors
insulators
Temperature
optoelectronic devices
locking
graphene
transistors
transition metals

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Atomic and Molecular Physics, and Optics
  • Biomedical Engineering
  • Materials Science(all)
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this

Cha, Soonyoung ; Noh, Minji ; Kim, Jehyun ; Son, Jangyup ; Bae, Hyemin ; Lee, Doeon ; Kim, Hoil ; Lee, Jekwan ; Shin, Ho Seung ; Sim, Sangwan ; Yang, Seunghoon ; Lee, Sooun ; Shim, Wooyoung ; Lee, Chul Ho ; Jo, Moon Ho ; Kim, Jun Sung ; Kim, Dohun ; Choi, Hyunyong. / Generation, transport and detection of valley-locked spin photocurrent in WSe2–graphene–Bi2Se3 heterostructures. In: Nature Nanotechnology. 2018 ; Vol. 13, No. 10. pp. 910-914.
@article{104bcc899af3454ba55c09905bc5d059,
title = "Generation, transport and detection of valley-locked spin photocurrent in WSe2–graphene–Bi2Se3 heterostructures",
abstract = "Quantum optoelectronic devices capable of isolating a target degree of freedom (DoF) from other DoFs have allowed for new applications in modern information technology. Many works on solid-state spintronics have focused on methods to disentangle the spin DoF from the charge DoF1, yet many related issues remain unresolved. Although the recent advent of atomically thin transition metal dichalcogenides (TMDs) has enabled the use of valley pseudospin as an alternative DoF2,3, it is nontrivial to separate the spin DoF from the valley DoF since the time-reversal valley DoF is intrinsically locked with the spin DoF4. Here, we demonstrate lateral TMD–graphene–topological insulator hetero-devices with the possibility of such a DoF-selective measurement. We generate the valley-locked spin DoF via a circular photogalvanic effect in an electric-double-layer WSe2 transistor. The valley-locked spin photocarriers then diffuse in a submicrometre-long graphene layer, and the spin DoF is measured separately in the topological insulator via non-local electrical detection using the characteristic spin–momentum locking. Operating at room temperature, our integrated devices exhibit a non-local spin polarization degree of higher than 0.5, providing the potential for coupled opto-spin–valleytronic applications that independently exploit the valley and spin DoFs.",
author = "Soonyoung Cha and Minji Noh and Jehyun Kim and Jangyup Son and Hyemin Bae and Doeon Lee and Hoil Kim and Jekwan Lee and Shin, {Ho Seung} and Sangwan Sim and Seunghoon Yang and Sooun Lee and Wooyoung Shim and Lee, {Chul Ho} and Jo, {Moon Ho} and Kim, {Jun Sung} and Dohun Kim and Hyunyong Choi",
year = "2018",
month = "10",
day = "1",
doi = "10.1038/s41565-018-0195-y",
language = "English",
volume = "13",
pages = "910--914",
journal = "Nature Nanotechnology",
issn = "1748-3387",
publisher = "Nature Publishing Group",
number = "10",

}

Cha, S, Noh, M, Kim, J, Son, J, Bae, H, Lee, D, Kim, H, Lee, J, Shin, HS, Sim, S, Yang, S, Lee, S, Shim, W, Lee, CH, Jo, MH, Kim, JS, Kim, D & Choi, H 2018, 'Generation, transport and detection of valley-locked spin photocurrent in WSe2–graphene–Bi2Se3 heterostructures', Nature Nanotechnology, vol. 13, no. 10, pp. 910-914. https://doi.org/10.1038/s41565-018-0195-y

Generation, transport and detection of valley-locked spin photocurrent in WSe2–graphene–Bi2Se3 heterostructures. / Cha, Soonyoung; Noh, Minji; Kim, Jehyun; Son, Jangyup; Bae, Hyemin; Lee, Doeon; Kim, Hoil; Lee, Jekwan; Shin, Ho Seung; Sim, Sangwan; Yang, Seunghoon; Lee, Sooun; Shim, Wooyoung; Lee, Chul Ho; Jo, Moon Ho; Kim, Jun Sung; Kim, Dohun; Choi, Hyunyong.

In: Nature Nanotechnology, Vol. 13, No. 10, 01.10.2018, p. 910-914.

Research output: Contribution to journalLetter

TY - JOUR

T1 - Generation, transport and detection of valley-locked spin photocurrent in WSe2–graphene–Bi2Se3 heterostructures

AU - Cha, Soonyoung

AU - Noh, Minji

AU - Kim, Jehyun

AU - Son, Jangyup

AU - Bae, Hyemin

AU - Lee, Doeon

AU - Kim, Hoil

AU - Lee, Jekwan

AU - Shin, Ho Seung

AU - Sim, Sangwan

AU - Yang, Seunghoon

AU - Lee, Sooun

AU - Shim, Wooyoung

AU - Lee, Chul Ho

AU - Jo, Moon Ho

AU - Kim, Jun Sung

AU - Kim, Dohun

AU - Choi, Hyunyong

PY - 2018/10/1

Y1 - 2018/10/1

N2 - Quantum optoelectronic devices capable of isolating a target degree of freedom (DoF) from other DoFs have allowed for new applications in modern information technology. Many works on solid-state spintronics have focused on methods to disentangle the spin DoF from the charge DoF1, yet many related issues remain unresolved. Although the recent advent of atomically thin transition metal dichalcogenides (TMDs) has enabled the use of valley pseudospin as an alternative DoF2,3, it is nontrivial to separate the spin DoF from the valley DoF since the time-reversal valley DoF is intrinsically locked with the spin DoF4. Here, we demonstrate lateral TMD–graphene–topological insulator hetero-devices with the possibility of such a DoF-selective measurement. We generate the valley-locked spin DoF via a circular photogalvanic effect in an electric-double-layer WSe2 transistor. The valley-locked spin photocarriers then diffuse in a submicrometre-long graphene layer, and the spin DoF is measured separately in the topological insulator via non-local electrical detection using the characteristic spin–momentum locking. Operating at room temperature, our integrated devices exhibit a non-local spin polarization degree of higher than 0.5, providing the potential for coupled opto-spin–valleytronic applications that independently exploit the valley and spin DoFs.

AB - Quantum optoelectronic devices capable of isolating a target degree of freedom (DoF) from other DoFs have allowed for new applications in modern information technology. Many works on solid-state spintronics have focused on methods to disentangle the spin DoF from the charge DoF1, yet many related issues remain unresolved. Although the recent advent of atomically thin transition metal dichalcogenides (TMDs) has enabled the use of valley pseudospin as an alternative DoF2,3, it is nontrivial to separate the spin DoF from the valley DoF since the time-reversal valley DoF is intrinsically locked with the spin DoF4. Here, we demonstrate lateral TMD–graphene–topological insulator hetero-devices with the possibility of such a DoF-selective measurement. We generate the valley-locked spin DoF via a circular photogalvanic effect in an electric-double-layer WSe2 transistor. The valley-locked spin photocarriers then diffuse in a submicrometre-long graphene layer, and the spin DoF is measured separately in the topological insulator via non-local electrical detection using the characteristic spin–momentum locking. Operating at room temperature, our integrated devices exhibit a non-local spin polarization degree of higher than 0.5, providing the potential for coupled opto-spin–valleytronic applications that independently exploit the valley and spin DoFs.

UR - http://www.scopus.com/inward/record.url?scp=85050570487&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85050570487&partnerID=8YFLogxK

U2 - 10.1038/s41565-018-0195-y

DO - 10.1038/s41565-018-0195-y

M3 - Letter

VL - 13

SP - 910

EP - 914

JO - Nature Nanotechnology

JF - Nature Nanotechnology

SN - 1748-3387

IS - 10

ER -