Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade laser.
Opt Express
; 21(25): 30401-14, 2013 Dec 16.
Article
en En
| MEDLINE
| ID: mdl-24514618
ABSTRACT
Utilizing a broadly-tunable external cavity quantum cascade laser for scattering-type scanning near-field optical microscopy (s-SNOM), we measure infrared spectra of particles of explosives by probing characteristic nitro-group resonances in the 7.1-7.9 µm wavelength range. Measurements are presented with spectral resolution of 0.25 cm(-1), spatial resolution of 25 nm, sensitivity better than 100 attomoles, and at a rapid acquisition time of 90 s per spectrum. We demonstrate high reproducibility of the acquired s-SNOM spectra with very high signal-to-noise ratios and relative noise of <0.02 in self-homodyne detection.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Transductores
/
Espectroscopía Infrarroja Corta
/
Sustancias Explosivas
/
Rayos Láser
/
Microquímica
Idioma:
En
Revista:
Opt Express
Asunto de la revista:
OFTALMOLOGIA
Año:
2013
Tipo del documento:
Article