Room-Temperature Active Modulation of Valley Dynamics in a Monolayer Semiconductor through Chiral Purcell Effects

Zilong Wu, Jingang Li, Xiaotian Zhang, Joan M. Redwing, Yuebing Zheng

Research output: Contribution to journalArticle

Abstract

Spin-dependent contrasting phenomena at K and K′ valleys in monolayer semiconductors have led to addressable valley degree of freedom, which is the cornerstone for emerging valleytronic applications in information storage and processing. Tunable and active modulation of valley dynamics in a monolayer WSe2 is demonstrated at room temperature through controllable chiral Purcell effects in plasmonic chiral metamaterials. The strong spin-dependent modulation on the spontaneous decay of valley excitons leads to tunable handedness and spectral shift of valley-polarized emission, which is analyzed and predicted by an advanced theoretical model and further confirmed by experimental measurements. Moreover, large active spectral tuning (≈24 nm) and reversible ON/OFF switching of circular polarization of emission are achieved by the solvent-controllable thickness of the dielectric spacer in the metamaterials. With the on-demand and active tunability in valley-polarized emission, chiral Purcell effects can provide new strategies to harness valley excitons for applications in ultrathin valleytronic devices.

Original languageEnglish (US)
Article number1904132
JournalAdvanced Materials
Volume31
Issue number49
DOIs
StatePublished - Dec 1 2019

Fingerprint

Metamaterials
Excitons
Monolayers
Modulation
Semiconductor materials
Circular polarization
Tuning
Data storage equipment
Temperature
LDS 751

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

@article{29f55bb37e124a6a92b57b24b3528f9e,
title = "Room-Temperature Active Modulation of Valley Dynamics in a Monolayer Semiconductor through Chiral Purcell Effects",
abstract = "Spin-dependent contrasting phenomena at K and K′ valleys in monolayer semiconductors have led to addressable valley degree of freedom, which is the cornerstone for emerging valleytronic applications in information storage and processing. Tunable and active modulation of valley dynamics in a monolayer WSe2 is demonstrated at room temperature through controllable chiral Purcell effects in plasmonic chiral metamaterials. The strong spin-dependent modulation on the spontaneous decay of valley excitons leads to tunable handedness and spectral shift of valley-polarized emission, which is analyzed and predicted by an advanced theoretical model and further confirmed by experimental measurements. Moreover, large active spectral tuning (≈24 nm) and reversible ON/OFF switching of circular polarization of emission are achieved by the solvent-controllable thickness of the dielectric spacer in the metamaterials. With the on-demand and active tunability in valley-polarized emission, chiral Purcell effects can provide new strategies to harness valley excitons for applications in ultrathin valleytronic devices.",
author = "Zilong Wu and Jingang Li and Xiaotian Zhang and Redwing, {Joan M.} and Yuebing Zheng",
year = "2019",
month = "12",
day = "1",
doi = "10.1002/adma.201904132",
language = "English (US)",
volume = "31",
journal = "Advanced Materials",
issn = "0935-9648",
publisher = "Wiley-VCH Verlag",
number = "49",

}

Room-Temperature Active Modulation of Valley Dynamics in a Monolayer Semiconductor through Chiral Purcell Effects. / Wu, Zilong; Li, Jingang; Zhang, Xiaotian; Redwing, Joan M.; Zheng, Yuebing.

In: Advanced Materials, Vol. 31, No. 49, 1904132, 01.12.2019.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Room-Temperature Active Modulation of Valley Dynamics in a Monolayer Semiconductor through Chiral Purcell Effects

AU - Wu, Zilong

AU - Li, Jingang

AU - Zhang, Xiaotian

AU - Redwing, Joan M.

AU - Zheng, Yuebing

PY - 2019/12/1

Y1 - 2019/12/1

N2 - Spin-dependent contrasting phenomena at K and K′ valleys in monolayer semiconductors have led to addressable valley degree of freedom, which is the cornerstone for emerging valleytronic applications in information storage and processing. Tunable and active modulation of valley dynamics in a monolayer WSe2 is demonstrated at room temperature through controllable chiral Purcell effects in plasmonic chiral metamaterials. The strong spin-dependent modulation on the spontaneous decay of valley excitons leads to tunable handedness and spectral shift of valley-polarized emission, which is analyzed and predicted by an advanced theoretical model and further confirmed by experimental measurements. Moreover, large active spectral tuning (≈24 nm) and reversible ON/OFF switching of circular polarization of emission are achieved by the solvent-controllable thickness of the dielectric spacer in the metamaterials. With the on-demand and active tunability in valley-polarized emission, chiral Purcell effects can provide new strategies to harness valley excitons for applications in ultrathin valleytronic devices.

AB - Spin-dependent contrasting phenomena at K and K′ valleys in monolayer semiconductors have led to addressable valley degree of freedom, which is the cornerstone for emerging valleytronic applications in information storage and processing. Tunable and active modulation of valley dynamics in a monolayer WSe2 is demonstrated at room temperature through controllable chiral Purcell effects in plasmonic chiral metamaterials. The strong spin-dependent modulation on the spontaneous decay of valley excitons leads to tunable handedness and spectral shift of valley-polarized emission, which is analyzed and predicted by an advanced theoretical model and further confirmed by experimental measurements. Moreover, large active spectral tuning (≈24 nm) and reversible ON/OFF switching of circular polarization of emission are achieved by the solvent-controllable thickness of the dielectric spacer in the metamaterials. With the on-demand and active tunability in valley-polarized emission, chiral Purcell effects can provide new strategies to harness valley excitons for applications in ultrathin valleytronic devices.

UR - http://www.scopus.com/inward/record.url?scp=85074099446&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85074099446&partnerID=8YFLogxK

U2 - 10.1002/adma.201904132

DO - 10.1002/adma.201904132

M3 - Article

AN - SCOPUS:85074099446

VL - 31

JO - Advanced Materials

JF - Advanced Materials

SN - 0935-9648

IS - 49

M1 - 1904132

ER -