Coupling of Photon Emitters in Monolayer WS2 with a Photonic Waveguide Based on Bound States in the Continuum

Xiao-Jing Liu; Yue Yu; Di Liu; Qi-Long Cui; Xiaozhuo Qi; Yang Chen; Guangyuan Qu; Li Song; Guo-Ping Guo; Guang-Can Guo; Xiankai Sun; Xi-Feng Ren

doi:10.1021/acs.nanolett.2c05034

Coupling of Photon Emitters in Monolayer WS₂ with a Photonic Waveguide Based on Bound States in the Continuum

Nano Lett. 2023 Apr 26;23(8):3209-3216. doi: 10.1021/acs.nanolett.2c05034. Epub 2023 Apr 11.

Authors

Xiao-Jing Liu^{1

2

3}, Yue Yu⁴, Di Liu^{1

2

3}, Qi-Long Cui⁵, Xiaozhuo Qi⁶, Yang Chen^{1

2

3}, Guangyuan Qu⁷, Li Song⁵, Guo-Ping Guo^{1

2

3}, Guang-Can Guo^{1

2

3}, Xiankai Sun⁴, Xi-Feng Ren^{1

2

3}

Affiliations

¹ CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, 230026, China.
² CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China.
³ Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China.
⁴ Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin Hong Kong SAR, China.
⁵ National Synchrotron Radiation Laboratory, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui 230029, China.
⁶ School of Physical Science and Technology, Tiangong University, Tianjin 300387, China.
⁷ School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.

PMID: 37040479
DOI: 10.1021/acs.nanolett.2c05034

Abstract

On-chip light sources are an essential component of scalable photonic integrated circuits (PICs), and coupling between light sources and waveguides has attracted a great deal of attention. Photonic waveguides based on bound states in the continuum (BICs) allow optical confinement in a low-refractive-index waveguide on a high-refractive-index substrate and thus can be employed for constructing PICs. In this work, we experimentally demonstrated that the photoluminescence (PL) from a monolayer of tungsten sulfide (WS₂) could be coupled into a BIC waveguide on a lithium-niobate-on-insulator (LNOI) substrate. Using finite-difference time-domain simulations, we numerically obtained a coupling efficiency of ∼2.3% for an in-plane-oriented dipole and a near-zero loss at a wavelength of 620 nm. By breaking through the limits of 2D-material integration with conventional photonic architectures, our work offers a new perspective for light-matter coupling in monolithic PICs.

Keywords: bound states in the continuum; lithium niobate on insulator; photon emitters; tungsten sulfide.