Nanoparticle trapping and characterization using open microcavities

Journal article

Characterization and trapping of nanoparticles in solution is of great importance for lab-on-a-chip applications in biomedical, environmental and materials sciences. Devices are now starting to emerge allowing such manipulations and investigations in realtime. Better insights into the interaction between the nanoparticle and the optical trap is therefore necessary in order to move forward in this field. In this work, we present a new kind of nano-tweezers based on open microcavities. We show that by monitoring the cavity mode wavelength shift as the particle diffuses through the cavity, it is possible to establish both the nanoparticle polarizability and its coefficient of friction. Additionally, our experiment provides a deep insight in the interaction between the nanoparticle and the cavity mode. The technique has built-in calibration of the trap strength and spring constant, making it attractive for practical applications. This work illustrates the potential of such optical microcavities for future developments in nanoparticle sensors and lab-on-a-chip devices.

Authors: Trichet, A; Dolan, P; James, D; Hughes, G; Vallance, C

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Chemical Society
• Journal: Nano Letters
• Volume: 16
• Issue: 10
• Pages: 6172–6177
• Publication date: 2016-09-21
• Acceptance date: 2016-09-21
• DOI: 10.1021/acs.nanolett.6b02433
• EISSN: 1530-6992
• ISSN: 1530-6984
• Keywords: optical trapping; nanophotonics; nanotweezer; nanoparticle; sensor; microcavity