Near-field deformation of a liquid interface by atomic force microscopy

Caroline Mortagne (1, 2) , Véronique Chireux (1) , René Ledesma Alonso (3) , Maëlle Ogier (1) , Frédéric Risso (1) , Thierry Ondarçuhu (1, 2) , Dominique Legendre (1) , Philippe Tordjeman (1)

1 IMFT - Institut de mécanique des fluides de Toulouse
2 CEMES - Centre d'élaboration de matériaux et d'études structurales
3 Universidad de Quintana Roo

We experiment the interaction between a liquid puddle and a spherical probe by Atomic Force Microscopy (AFM) for a probe radius R ranging from 10 nm to 30 μm. We have developed a new experimental setup by coupling an AFM with a high-speed camera and an inverted optical microscope. Interaction force-distance curves (in contact mode) and frequency shift–distance curves (in frequency modulation mode) are measured for different bulk model liquids for which the probe-liquid Hamaker constant Hpl is known. The experimental results, analyzed in the frame of the theoretical model developed in Phys. Rev. Lett. 108, 106104 (2012) and Phys. Rev. E 85, 061602 (2012), allow to determine the “jump-to-contact” critical distance dmin below which the liquid jumps and wets the probe. Comparison between theory and experiments shows that the probe-liquid interaction at nanoscale is controlled by the liquid interface deformation. This work shows a very good agreement between the theoretical model and the experiments and paves the way to experimental studies of liquids at the nanoscale.

Mots clés: Atomic Force Microscopy; Liquid interface; Jump-to-contact; Near-field interaction

Domaines: Mécanique des fluides [physics.class-ph]

Caroline Mortagne, Véronique Chireux, René Ledesma Alonso, Maëlle Ogier, Frédéric Risso, et al.. Near-field deformation of a liquid interface by atomic force microscopy. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2017, vol. 96 (n° 1), pp. 012802/1-012802/7. ⟨10.1103/PhysRevE.96.012802⟩. ⟨hal-01597280⟩