|2001-2004:||Physical Optics Laboratory - ESPCI (Paris, France)|
|Apertureless scanning near-field optical microscopy
with or without laser source
|- F. Formanek et al., "Imaging subwavelength holes using
an apertureless near-field scanning optical microscope" |
J. Appl. Phys. 93, 9548 (2003). PDF
- F. Formanek et al., "Thermal radiation scanning tunneling microscopy" (熱放射走査型トンネル顕微鏡)
Nature 444, 740 (2006).
This work was realized as part of my PhD Thesis of the Pierre et Marie Curie University, Paris VI, at the Physical Optics Laboratory in ESPCI (Ecole Supérieure de Physique et de Chimie Industrielles) engineer school of Paris.
|"Development of a near-field scanning optical microscope|
working in the visible, in the infrared, with or without illumination"
|The jury was composed of Prof. Claude FABRE (chair), Dr. Daniel COURJON (examiner), Prof. Jean-Jacques GREFFET (examiner), Dr. Bernard QUERLEUX, Prof. Claude BOCCARA (thesis supervisor) and Dr. Yannick DE WILDE (thesis supervisor).|
The main part of my research concerned the development of a near-field optical microscope based on a quartz tuning-fork and an apertureless tungsten tip operating in tapping mode. This instrument is able to work in various configurations, especially in the infrared as sketched below:
In this configuration, the beam from a CO2 laser (λ = 10.6 µm) is focused at grazing incidence onto the tip apex by a ZnSe lens. The field scattered by the tip is collected by a Cassegrain objective (36X, NA = 0.5) made of two spherical gold mirrors and sent towards an HgCdTe nitrogen cooled detector connected to a lock-in amplifier operating at the fundamental oscillation frequency (Ω) of the tip or at its higher harmonics. The lock-in enables to extract the weak contribution of the near-field signal from the far-field background.
More recently, we have transformed the infrared configuration into a "thermal radiation scanning tunneling microscope" (TRSTM) to detect thermal infrared evanescent fields naturally emitted by a surface. With this new kind of near-field microscope operating without any external illumination, we were able to observe thermally excited surface plasmons and to demonstrate spatial coherence effects in near-field thermal emission.
- My article about dyed human hair, written in collaboration with people from L'Oréal, is now published in Journal of Microscopy.