Kuan-Chang Chiu

Observation of Interlayer Phonon Modes in Van Der Waals Heterostructures

We have investigated the vibrational properties of van der Waals heterostructures of monolayer transition metal dichalcogenides (TMDs), specifically

Promising electron field emitters composed of conducting perovskite LaNiO3 shells on ZnO nanorod arrays

\mathrm{Mo}{\mathrm{S}}_{2}/\mathrm{WS}{\mathrm{e}}_{2}

Prominent electric properties of BiFeO3 shells sputtered on ZnO-nanorod cores with LaNiO3 buffer layers

and

Synthesis and Application of Monolayer Semiconductors (June 2015)

\mathrm{MoS}{\mathrm{e}}_{2}/\mathrm{Mo}{\mathrm{S}}_{2}

Synthesis of In‐Plane Artificial Lattices of Monolayer Multijunctions

heterobilayers and twisted

Enabling monolithic 3D image sensor using large-area monolayer transition metal dichalcogenide and logic/memory hybrid 3D + IC

\mathrm{Mo}{\mathrm{S}}_{2}

Phase-driven magneto-electrical characteristics of single-layer MoS2

bilayers, by means of ultralow-frequency Raman spectroscopy. We discovered Raman features (at

Compensation of N-Related Defects in p-Type Al-N Codoped MgZnO Films

30\char21{}40\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}

Monolayer Multijunctions: Synthesis of In-Plane Artificial Lattices of Monolayer Multijunctions (Adv. Mater. 7/2018)

) that arise from the layer-breathing mode (LBM) vibration between the two incommensurate TMD monolayers in these structures. The LBM Raman intensity correlates strongly with the suppression of photoluminescence that arises from interlayer charge transfer. The LBM is generated only in bilayer areas with direct layer-layer contact and an atomically clean interface. Its frequency also evolves systematically with the relative orientation between the two layers. Our research demonstrates that the LBM can serve as a sensitive probe to the interface environment and interlayer interactions in van der Waals materials.

Electron Field Emission of Geometrically Modulated Monolayer Semiconductors

We report a semiconductor–perovskite composite system with promising field emission properties. The composite system was fabricated by sputtering perovskite LaNiO3 (LNO) shells on one dimensional (1D) well-aligned hydrothermally produced ZnO nanorod arrays (ZNAs). The ZNA–LNO core–shell hetero-structures were demonstrated to be much more efficient field emitters than ZNAs. Since the work function of LNO (4.5 eV) is lower than that of ZnO (5.3 eV), a shallow well is formed in thermal equilibrium in the ZNA–LNO heterojunction. When an electric field is applied, the produced well is of much benefit for the flow of electrons from the GZO seed layers through the ZNA to the LNO shells. Consequently, the emission of electrons into vacuum by tunneling is easily realized due to the low work function of the LNO coatings. Our 1D semiconductor–perovskite composite system provides a prospect for the development of practical field emission electron sources.