optoelectronics: Exploring nanoscale science and technology through semiconductor nanowires*

Abstract: Semiconductor nanowires (NWs) represent an ideal system for investigating low-dimensional physics and are expected to play an important role as both interconnects and functional device elements in nanoscale electronic and optoelectronic devices. Here we re-view a series of key advances defining a new paradigm of bottom-up assembling integrated nanosystems using semiconductor NW building blocks. We first introduce a general ap-proach for the synthesis of a broad range of semiconductor NWs with precisely controlled chemical composition, physical dimension, and electronic, optical properties using a metal cluster-catalyzed vapor–liquid–solid growth mechanism. Subsequently, we describe rational strategies for the hierarchical assembly of NW building blocks into functional devices and complex architectures based on electric field or micro-fluidic flow. Next, we discuss a vari-ety of new nanoscale electronic device concepts including crossed NW p-n diode and crossed NW field effect transistors (FETs). Reproducible assembly of these scalable crossed NW de-vice elements enables a catalog of integrated structures, including logic gates and computa-tional circuits. Lastly, we describe a wide range of photonic and optoelectronic devices, in-cluding nanoscale light-emitting diodes (nanoLEDs), multicolor LED arrays, integrated nanoLED–nanoFET arrays, single nanowire waveguide, and single nanowire nanolaser. The potential application of these nanoscale light sources for chemical and biological analyses is discussed