A nanometre-scale resolution interference-based probe of interfacial phenomena between microscopic objects and surfaces

Abstract

Interferometric techniques have proven useful to infer proximity and local surface profiles of microscopic objects near surfaces. But a critical trade-off emerges between accuracy and mathematical complexity when these methods are applied outside the vicinity of closest approach. Here we introduce a significant advancement that enables reflection interference contrast microscopy to provide nearly instantaneous reconstruction of an arbitrary convex object’s contour next to a bounding surface with nanometre resolution, making it possible to interrogate microparticle/surface interaction phenomena at radii of curvature 1,000 times smaller than those accessible by the conventional surface force apparatus. The unique view-from-below perspective of reflection interference contrast microscopy also reveals previously unseen deformations and allows the first direct observation of femtolitre-scale capillary condensation dynamics underneath micron-sized particles. Our implementation of reflection interference contrast microscopy provides a generally applicable nanometre-scale resolution tool that can be potentially exploited to dynamically probe ensembles of objects near surfaces so that statistical/probabilistic behaviour can be realistically captured.

Evaluation of energy dissipation involving adhesion hysteresis in spherical contact between a glass lens and a PDMS block

“…However, the relationship does not represent how the total energy dissipation changes during the contact process, and the mechanism of adhesion hysteresis is still on discussion assuming capillary condensation or adsorbed layer, etc. [17][18][19][22][23][24][25]. In this paper, a polydimethylsiloxane (PDMS) block is used as the elastic materials, the contact processes between the PDMS and a glass lens have been investigated to evaluate the energy dissipation.…”

Micron‐scale wedge thin films prepared by plasma enhanced chemical vapor deposition

“…However, it is in the field of optics and photonics where nano‐/micro wedge or tip structures are having a major scientific and technological impact. For example, interference fringes associated to the wedge/convex surfaces of water microdroplets have been used to unravel the nature of microparticle/surface interactions . Moreover, in miniaturized lab‐on‐a‐chip refractive index liquid detectors, microcavities in a wedge configuration have been used to progressively vary the optical path of the system, whereas in plasmonics, the use of nano/micro tips in wedge structures is pervasive for a large variety of applications (nanofocussing, light guiding, etc.)…”

“…For example, interference fringes associated to the wedge/convex surfaces of water microdroplets have been used to unravel the nature of microparticle/surface interactions. [8] Moreover, in miniaturized lab-on-a-chip refractive index liquid detectors, microcavities in a wedge configuration have been used to progressively vary the optical path of the system, [9] whereas in plasmonics, the use of nano/micro tips in wedge structures is pervasive for a large variety of applications (nanofocussing, light guiding, etc.). [10,11] Similarly, hybrid plasmonic wedge structures have been recently proposed for THz wave guiding.…”

Colloidal crystals and water: Perspectives on liquid–solid nanoscale phenomena in wet particulate media

“…It can also complement the explanation of a threshold in adhesion experiments between smooth surfaces [108,138,144], in which a minimum wetting film is claimed to be necessary for the formation of the capillary bridge. On the other hand, if suction is slow, it may contribute to sluggish growth of bridges [138,139,145], also leading to aging phenomena [30,39,146], which is often attributed to thermally activated capillary condensation [39,146]. Nanoscale topology and capillarity will have a great impact on imbibition and drainage in particulate media [147,148], fabrication and deterioration of building materials [149], water retention in soils [150] and water treatment [ 151 ].…”