Surface Plasmon Radiation Forces published in Phys. Rev. Lett.

Surface plasmon radiation forces

Surface plasmon radiation forces
Giovanni Volpe, Romain Quidant, Gonçal Badenes & Dmitri Petrov
Physical Review Letters 96(23), 238101 (2006)
DOI: 10.1103/PhysRevLett.96.238101

We report the first experimental observation of momentum transfer from a surface plasmon to a single dielectric sphere. Using a photonic force microscope, we measure the plasmon radiation forces on different polystyrene beads as a function of their distance from the metal surface. We show that the force magnitude at resonance is strongly enhanced compared to a nonresonant illumination. Measurements performed as a function of the probe particle size indicate that optical manipulation by plasmon fields has a strong potential for optical sorting.

Dynamics of a Growing Cell in an Optical Trap published in Appl. Phys. Lett.

Dynamics of a growing cell in an optical trap

Dynamics of a growing cell in an optical trap
Giovanni Volpe, Gajendra Pratap Singh & Dmitri Petrov
Applied Physics Letters 88(23), 231106 (2006)
DOI: 10.1063/1.2213015

We analyze the forward scattered light from a single optically trapped cellduring its growth. We show that the cell continues adjusting itself to the applied optical force because of the growth processes, and hence it keeps changing its orientation in the trap. We point out the importance of taking this variation into account in the interpretation of spectroscopic data. This method can also be used as a means for cell identification and cell sorting.