Dr. Zhe Wang from NUS, in collaboration with international researchers led by Prof Goki Eda, recently discovered that a single monolayer semiconductor integrated into a plasmonic tunnel junction exhibits electroluminescence with photon energies exceeding the excitation electrical potential. The researchers found that this unusual phenomenon is triggered by highly energetic charge carriers generated by a small fraction of electrons undergoing quantum tunneling. The discovery extends the principles of upconversion, previously explored in small molecules, to a macroscopic device system, offering new insights into the realization of unconventional device functionalities. This work was published in Nature Nanotechnology (April 2024).

Quantum Tunneling Powers High-Energy Light Emission