Substrate-enhanced infrared near-field spectroscopy

被引：102

作者：

Aizpurua, Javier ^{[1
]}

Taubner, Thomas ^{[2
,3
]}

Javier Garcia de Abajo, F. ^{[4
]}

Brehm, Markus ^{[5
]}

Hillenbrand, Rainer ^{[3
,6
]}

机构：

[1] Donostia Int Phys Ctr, San Sebastian 20018, Spain

[2] Stanford Univ, Stanford, CA 94305 USA

[3] Max Planck Inst Biochem, Nanophoton Grp, D-82152 Martinsried, Germany

[4] CSIC, Inst Opt, E-28006 Madrid, Spain

[5] Max Planck Inst Biochem, Abt Mol Strukturbiol, D-82152 Martinsried, Germany

[6] CIC NanoGUNE Consolider, Donostia San Sebastian 20009, Spain

来源：

OPTICS EXPRESS | 2008年 / 16卷 / 03期

关键词：

D O I：

10.1364/OE.16.001529

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

We study the amplitude and phase signals detected in infrared scattering-type near field optical microscopy (s-SNOM) when probing a thin sample layer on a substrate. We theoretically describe this situation by solving the electromagnetic scattering of a dipole near a planar sample consisting of a substrate covered by thin layers. We perform calculations to describe the effect of both weakly (Si and SiO2) and strongly (Au) reflecting substrates on the spectral s-SNOM signal of a thin PMMA layer. We theoretically predict, and experimentally confirm an enhancement effect in the polymer vibrational spectrum when placed on strongly reflecting substrates. We also calculate the scattered fields for a resonant tip-substrate interaction, obtaining a dramatic enhancement of the signal amplitude and spectroscopic contrast of the sample layer, together with a change of the spectral line shape. The enhanced contrast opens the possibility to perform ultra-sensitive near field infrared spectroscopy of monolayers and biomolecules. (c) 2008 Optical Society of America.

引用

页码：1529 / 1545

页数：17

共 49 条

[1] Monolayer-sensitive infrared imaging of DNA stripes using apertureless near-field microscopy [J].