Quantum-Confined Stark Effect of Individual Defects in a van der Waals Heterostructure

Chitraleema Chakraborty, Kenneth M. Goodfellow, Sajal Dhara, Anthony Yoshimura, Vincent Meunier, A. Nick Vamivakas

Research output: Contribution to journalArticlepeer-review

84 Scopus citations

Abstract

The optical properties of atomically thin semiconductor materials have been widely studied because of the isolation of monolayer transition metal dichalcogenides (TMDCs). They have rich optoelectronic properties owing to their large direct bandgap, the interplay between the spin and the valley degree of freedom of charge carriers, and the recently discovered localized excitonic states giving rise to single photon emission. In this Letter, we study the quantum-confined Stark effect of these localized emitters present near the edges of monolayer tungsten diselenide (WSe2). By carefully designing sequences of metallic (graphene), insulating (hexagonal boron nitride), and semiconducting (WSe2) two-dimensional materials, we fabricate a van der Waals heterostructure field effect device with WSe2 hosting quantum emitters that is responsive to external static electric field applied to the device. A very efficient spectral tunability up to 21 meV is demonstrated. Further, evaluation of the spectral shift in the photoluminescence signal as a function of the applied voltage enables us to extract the polarizability volume (up to 2000 Å3) as well as information on the dipole moment of an individual emitter. The Stark shift can be further modulated on application of an external magnetic field, where we observe a flip in the sign of dipole moment possibly due to rearrangement of the position of electron and hole wave functions within the emitter.

Original languageEnglish (US)
Pages (from-to)2253-2258
Number of pages6
JournalNano letters
Volume17
Issue number4
DOIs
StatePublished - Apr 12 2017

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • General Chemistry
  • General Materials Science
  • Condensed Matter Physics
  • Mechanical Engineering

Fingerprint

Dive into the research topics of 'Quantum-Confined Stark Effect of Individual Defects in a van der Waals Heterostructure'. Together they form a unique fingerprint.

Cite this