Towards an optical coupler using fine-wire： a study of the photovoltaic effect of a heterojunction formed in a single fine-wire of tungsten oxides

• Published in: Chinese physics B 2010-03, Vol.19 (3), p.557-562, Article 037803
• Main Author: 陈尚辉 陈建 邓少芝 许宁生
• Format: Article
• Language: English
• Subjects: Heterojunctions; Joining; Nanocomposites; Nanomaterials; Nanostructure; Optical communication; Photovoltaic effect; Tungsten oxides; 光伏效应; 光电子集成电路; 光耦合器; 异质结; 最大输出功率; 氧化物; 细钨丝
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/19/3/037803

Nanodevices using the photovoltaic effect of a single nanowire have attracted growing interest. In this paper, we consider potential applications of the photovoltaic effect to optical signal coupling and optical power transmission, and report on the realization of a heterojunction formed between WO2 and WO3 in a fine-wire having a diameter on the micrometer scale. Using a laser beam of 514.5 nm as a signal source, the WO2-WO3 heterojunction yields a maximum output power of up to 37.4 pico watt per heterojunction. Fast responses （less than a second） of both photovoltaic voltage and current are also observed. In addition, we demonstrate that it is a simple and effective way to adapt a commercial Raman spectrometer for the combined functions of fabrication, material characterization and photovottaic measurement of an optical signal coupler and optical power transmitter based on a fine-wire. Our results show an attractive perspective of developing nanowire or fine-wire elements for coupling optical signals into and for powering a nanoelectronic or nano-optoelectronic integrated circuit that works under the condition of preventing it from directly electrically connecting with the optical coupler.