English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We have investigated photoconductive properties of single GermaniumNanowires(NWs)of diameter less than 100 nm in the spectral range of 300 to 1100nm showing ultra large peak Responsivity in excess of 10^{7}AW^{-1}.The NWswere grown by Vapor Liquid Solid method using Au nanoparticle as catalyst. Inthis report we discuss the likely origin of the ultra large responsivity thatmay arise from a combination of various physical effects which are a): Ge andGeO_{x} interface states which act as scavengers of electrons from thephoto-generated pairs,leaving the holes free to reach the electrodes,b)Schottky barrier at the metal and NW interface which gets lowered substantiallydue to carrier diffusion in contact region and (c) photodetector length beingsmall (approximately few {\mu}m), negligible loss of photogenerated carriersdue to recombination at defect sites. We have observed from power dependence ofthe optical gain that the gain is controlled by trap states. We find that thesurface of the nanowire has presence of a thin layer of GeO_{x} (as evidencedfrom HRTEM study) which provide interface states. It is observed that thesestate play a crucial role to provide a radial field for separation ofphotogenerated electron and hole pair which in turn leads to very higheffective photoconductive gain that reaches a very high at low illuminationdensity.

Broad Band Single Germanium Nanowire Photodetectors with Surface Oxide Controlled High Optical Gain