  Precise control of particle positioning is desirable in many optical
propulsion and sorting applications. Here, we develop an integrated platform
for particle manipulation consisting of a combined optical nanofibre and
optical tweezers system. Individual silica microspheres were introduced to the
nanofibre at arbitrary points using the optical tweezers, thereby producing
pronounced dips in the fibre transmission. We show that such consistent and
reversible transmission modulations depend on both particle and fibre diameter,
and can be used as a reference point for in situ nanofibre or particle size
measurement. Thence, we combine scanning electron microscope (SEM) size
measurements with nanofibre transmission data to provide calibration for
particle-based fibre assessment. This integrated optical platform provides a
method for selective evanescent field manipulation of micron-sized particles
and facilitates studies of optical binding and light-particle interaction
dynamics.
