Observation of site-controlled localized charged excitons in CrI3/WSe2 heterostructures

Abstract

Isolated spins are the focus of intense scientific exploration due to their potential role as qubits for quantum information science. Optical access to single spins, demonstrated in III-V semiconducting quantum dots, has fueled research aimed at realizing quantum networks. More recently, quantum emitters in atomically thin materials such as tungsten diselenide have been demonstrated to host optically addressable single spins by means of electrostatic doping the localized excitons. Electrostatic doping is not the only route to charging localized quantum emitters and another path forward is through band structure engineering using van der Waals heterojunctions. Critical to this second approach is to interface tungsten diselenide with other van der Waals materials with relative band-alignments conducive to the phenomenon of charge transfer. In this work we show that the Type-II band-alignment between tungsten diselenide and chromium triiodide can be exploited to excite localized charged excitons in tungsten diselenide. Leveraging spin-dependent charge transfer in the device, we demonstrate spin selectivity in the preparation of the spin-valley state of localized single holes. Combined with the use of strain-inducing nanopillars to coordinate the spatial location of tungsten diselenide quantum emitters, we uncover the possibility of realizing large-scale deterministic arrays of optically addressable spin-valley holes in a solid state platform.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 30, 2020
Source ID
10.1038/s41467-020-19262-2

Entities

People

  • Arunabh Mukherjee
  • Jie Shan
  • Kamran Shayan
  • Kin Fai Mak
  • Lizhong Li
  • Nick Vamivakas

Organizations

  • Air Force Office of Scientific Research
  • National Science Foundation
  • United States Department of Energy

Tags

Fields of Study

  • Physics

Readers

  • Plasma Physics.
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene
  • Quantum Computing
  • Quantum Science - Quantum Dots