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Observation of strongly enhanced photoluminescence from inverted cone-shaped silicon nanostructures. [corrected].

ABSTRACT: Silicon nanowires (SiNWs) attached to a wafer substrate are converted to inversely tapered silicon nanocones (SiNCs). After excitation with visible light, individual SiNCs show a 200-fold enhanced integral band-to-band luminescence as compared to a straight SiNW reference. Furthermore, the reverse taper is responsible for multifold emission peaks in addition to the relatively broad near-infrared (NIR) luminescence spectrum. A thorough numerical mode analysis reveals that unlike a SiNW the inverted SiNC sustains a multitude of leaky whispering gallery modes. The modes are unique to this geometry and they are characterized by a relatively high quality factor (Q ~ 1300) and a low mode volume (0.2

SUBMITTER: Schmitt SW

PROVIDER: S-EPMC4660596 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Observation of strongly enhanced photoluminescence from inverted cone-shaped silicon nanostructures. [corrected].

Schmitt Sebastian W SW Sarau George G Christiansen Silke S

Scientific reports 20151126

Silicon nanowires (SiNWs) attached to a wafer substrate are converted to inversely tapered silicon nanocones (SiNCs). After excitation with visible light, individual SiNCs show a 200-fold enhanced integral band-to-band luminescence as compared to a straight SiNW reference. Furthermore, the reverse taper is responsible for multifold emission peaks in addition to the relatively broad near-infrared (NIR) luminescence spectrum. A thorough numerical mode analysis reveals that unlike a SiNW the invert ...[more]

PMID: 26606890

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