Optical properties of plasmonic tunneling junctions

Abstract

Over the last century, quantum theories have revolutionized our understanding of material properties. One of the most striking quantum phenomena occurring in heterogeneous media is the quantum tunneling effect, where carriers can tunnel through potential barriers even if the barrier height exceeds the carrier energy. Interestingly, the tunneling process can be accompanied by absorption or emission of light. In most tunneling junctions made of noble metal electrodes these optical phenomena are governed by plasmonic modes, i.e. light-driven collective oscillations of surface electrons. In the emission process, plasmon excitation via inelastic tunneling electrons can improve the efficiency of photon generation resulting in bright nanoscale optical sources. On the other hand, the incident light can affect the tunneling behavior of plasmonic junctions as well, leading to phenomena such as optical rectification and induced photocurrent. Thus, plasmonic tunneling junctions provide a rich platform for investigating light-matter interactions paving the way for various applications, including nanoscale light sources, sensors, and chemical reactors. In this paper, we will introduce recent research progresses and promising applications based on the plasmonic tunneling junctions.

Construction of High Accuracy Machine Learning Interatomic Potential for Surface/Interface of Nanomaterials—A Review

“…Additionally, equivariant GNN-based MLIP have demonstrated the capability to drastically reduce data requirements for model training without sacrificing model accuracy. [89] Inorganic material surfaces Silicon [110,132,133,228] Carbon [106,[137][138][139][229][230][231] Phosphorus [232] Metal [146,[233][234][235][236] Alloy [237][238][239] Oxide [141,240,241] Nanoparticles a Metal [153,154,160] Alloy clusters [238] Other inorganic clusters [242] Supported nanoparticles [243][244][245] Gas environment Solid-gas [179,245,246] Liquid-gas [247] Solution environment Solid-liquid [186][187][188][189][190][191]193,[248][249][250] Nanoconfined environment …”

Light-Emitting Plasmonic Tunneling Junctions: Current Status and Perspectives

“…Through the radiative decay of surface plasmons excited by the IET process, the direct conversion of the electrons to photons in the visible and near-infrared range is realized. − However, it suffers a low electron-to-plasmon conversion efficiency, large wave vector mismatch between plasmons and free-space photons, and large nonradiative damping. , All these issues lead to an extremely low EQE in the range of 10 –7 to 10 –5 for planar MIM tunneling junctions, which limits the further applications of the light source. , Subsequently, the EQE can be enhanced by junction design, such as adjusting the barrier thickness to obtain high local density, increasing the surface roughness of the electrode to provide momentum matching, replacing one of the electrodes with a metal tip or subwavelength gratings, or introducing the resonant optical antennas into the junctions. ,,− Tunneling junctions with integrated optical antennas efficiently bridge the size mismatch between nanoscale volumes and far-field radiation. These are regarded as one primary approach to enhance the electron-to-photon conversion efficiency.…”

Analysis of the influencing factors of transmission coefficients based on ZnSe/BeTe heterojunction

“…According to quantum theory, an electron with energy E can pass through a potential barrier whose potential is higher than its energy. This is regarded as the quantum tunneling effect, which cannot be explained by classical physics theory [1,2]. Particularly, the multiple potential barrier structures have received significant attention worldwide due to their unique properties like miniband structures [3].…”