All-Graphene-Contact Electrically Pumped On-Demand Transferrable Nanowire Source

Abstract

On-demand NW light sources in a photonic integrated circuit (PIC) have faced several practical challenges. Here, we report on an all-graphene-contact, electrically pumped, on-demand transferrable NW source that is fabricated by implementing an all-graphene-contact approach in combination with a highly accurate microtransfer printing technique. A vertically p−i−n-doped top-down-fabricated semiconductor NW with optical gain structures is electrically pumped through the patterned multilayered graphene contacts. Electroluminescence (EL) spectroscopy results reveal that the electrically driven NW device exhibits strong EL emission between the contacts and displays waveguiding properties. Further, a single NW device is precisely integrated into an existing photonic waveguide to perform light coupling and waveguiding experiments. Three-dimensional numerical simulation results show a good agreement with experimental observations. We believe that our all-graphene-contact approach is readily applicable to various micro/nanostructures and devices, which facilitates stable electrical operation and thus extends their practical applicability in compact integrated circuits.

Atomic Hydrogen Annealing of Graphene on InAs Surfaces and Nanowires: Interface and Morphology Control for Optoelectronics and Quantum Technologies

“…Doubling of mobility has also recently been attributed to atomic hydrogen annealing, in NW devices for scalable quantum and optoelectronics . Finally, the tight folding properties of the graphene and the clean interface would open up interesting prospects for using graphene as a wrap-around gate electrode for quantum technologies . A large contact area is needed to achieve low resistance in the contacts, and well-defined electrical fields inside the NW depend on both tight and well-defined folding as well as the removal of oxide related defects that can charge and screen.…”

“…31 Finally, the tight folding properties of the graphene and the clean interface would open up interesting prospects for using graphene as a wrap-around gate electrode for quantum technologies. 24 A large contact area is needed to achieve low resistance in the contacts, and well-defined electrical fields inside the NW depend on both tight and welldefined folding as well as the removal of oxide related defects that can charge and screen. The present demonstration of interface control is thus a step toward realizing such applications.…”

“…16,17 Combining graphene with semiconductor NWs has been resulted in a wide range of interesting applications, such as transparent organic single crystal field-effect transistors, 7 NW devices with graphene electrodes, 8,19−21 high-responsivity graphene/InAs NW heterojunction photodetectors, 22 graphene-coated waveguides, 23 and photonic integrated sources. 24 To realize the full performance potential for these and many other applications, both morphology and graphene/semiconductor interface must be controlled. Defect-free interfaces are important to realize transport properties, enabling graphene plasmonics, quantum technologies, 25 and high optical efficiencies of these systems.…”

“…Metallic graphene and semiconducting III–V compound NWs are two classes of nanomaterials with very different properties. The inertness, extreme conductivity, − optical transparency, − and mechanical flexibility − of the graphene have made it a good candidate to be widely used as a potential high-performance electrode − and protective layer. , This can be combined with the excellent optical and transport properties of the III–V semiconductors, , with promises for optoelectronic and photovoltaic as well as quantum technology applications. , Combining graphene with semiconductor NWs has been resulted in a wide range of interesting applications, such as transparent organic single crystal field-effect transistors, NW devices with graphene electrodes, ,− high-responsivity graphene/InAs NW heterojunction photodetectors, graphene-coated waveguides, and photonic integrated sources . To realize the full performance potential for these and many other applications, both morphology and graphene/semiconductor interface must be controlled.…”

Highly Accurate Docking of a Photonic Crystal Nanolaser to a SiNx Waveguide by Transfer Printing

“…This improvement allows it to achieve sub-wavelength-level misalignment of wire-to-wire integration in PICs, as well as suitable for different dielectric or metallic nanophotonic structures ,,− onto different platforms. For example, highly efficient coupling can be achieved by integrating nanowires − or photonic crystal (PhC) nanobeam (NB) − light sources with silicon-based waveguides. Various alignment marks ,,− have been used to achieve misalignments of less than hundreds of nanometers, and careful feedback control associated with multiple marks has been reported to achieve misalignments of less than 100 nm .…”