TY - JOUR
T1 - Boosting Enhancement of the Electron–Phonon Coupling in Mixed Dimensional CdS/Graphene van der Waals Heterojunction
AU - Li, Zhonglin
AU - Guo, Shuai
AU - Weller, Dieter
AU - Quan, Sufeng
AU - Yu, Jing
AU - Wang, Runqiu
AU - Wu, Mengxuan
AU - Jiang, Jie
AU - Wang, Yingying
AU - Liu, Ruibin
N1 - Publisher Copyright:
© 2022 Wiley-VCH GmbH.
PY - 2022/4/14
Y1 - 2022/4/14
N2 - Electron–phonon coupling plays a key role in affecting the properties of the semiconducting nanostructures, such as providing the possibility for obtaining higher superconducting transition temperatures. Here, using Raman, temperature-dependent and polarized Raman scattering measurements, ultra-strong electron–phonon coupling in 1D CdS nanowires and 2D graphene heterostructures is demonstrated. The intensity ratio of 2LO/1LO mode in CdS nanowires provides a spectroscopy-based method to quantify electron–phonon coupling, the strength of which is temperature and polarization dependent. The intensity ratio mode of 2LO/1LO in heterostructure reached up to 8.95 when the incident laser polarization is parallel to the c-axis of the nanowire. It is ≈2.37 times higher than in an individual nanowire. In addition, in situ and time-resolved photoluminescence spectra demonstrate the dynamics of the exciton recombinations, providing a comprehensive understanding of the enhancement of electron–phonon coupling in heterostructures. Via optical waveguiding characterization, the graphene layer is demonstrated to not only be an ultrafast carrier transfer channel but also a low Fermi level channel that induces the formation of the built in electrical field, elevating the electron–phonon coupling. Such new mixed dimensional heterostructures illustrate a straightforward approach to enhance the electron–phonon coupling, which may be applied to many integrated superconducting photonic and optoelectronic devices.
AB - Electron–phonon coupling plays a key role in affecting the properties of the semiconducting nanostructures, such as providing the possibility for obtaining higher superconducting transition temperatures. Here, using Raman, temperature-dependent and polarized Raman scattering measurements, ultra-strong electron–phonon coupling in 1D CdS nanowires and 2D graphene heterostructures is demonstrated. The intensity ratio of 2LO/1LO mode in CdS nanowires provides a spectroscopy-based method to quantify electron–phonon coupling, the strength of which is temperature and polarization dependent. The intensity ratio mode of 2LO/1LO in heterostructure reached up to 8.95 when the incident laser polarization is parallel to the c-axis of the nanowire. It is ≈2.37 times higher than in an individual nanowire. In addition, in situ and time-resolved photoluminescence spectra demonstrate the dynamics of the exciton recombinations, providing a comprehensive understanding of the enhancement of electron–phonon coupling in heterostructures. Via optical waveguiding characterization, the graphene layer is demonstrated to not only be an ultrafast carrier transfer channel but also a low Fermi level channel that induces the formation of the built in electrical field, elevating the electron–phonon coupling. Such new mixed dimensional heterostructures illustrate a straightforward approach to enhance the electron–phonon coupling, which may be applied to many integrated superconducting photonic and optoelectronic devices.
KW - CdS/graphene
KW - Raman spectroscopy
KW - electron–phonon coupling
KW - mixed dimensional
KW - van der Waals heterostructure
UR - http://www.scopus.com/inward/record.url?scp=85124484887&partnerID=8YFLogxK
U2 - 10.1002/admi.202101893
DO - 10.1002/admi.202101893
M3 - Article
AN - SCOPUS:85124484887
SN - 2196-7350
VL - 9
JO - Advanced Materials Interfaces
JF - Advanced Materials Interfaces
IS - 11
M1 - 2101893
ER -