RESUMO
We experimentally studied a continuous time evolution of a "plasmonic" walker in a 1-dimensional lattice structure based on long-range surface plasmon polariton waveguides. The plasmonic walker exhibited a typical time evolution of a 1-dimensional quantum walk, which indicates that the plasmonic system is a potential platform to construct quantum walk simulators. By comparing experimental results to numerical simulations, the fidelity of the plasmonic quantum walk simulator is estimated to be > 0.96, which demonstrates that the plasmonic system can be a feasible platform for large-scale and high dimensional quantum walk simulators.
RESUMO
High-speed isolation of microparticles (e.g., microplastics, heavy metal particles, microbes, cells) from heterogeneous populations is the key element of high-throughput sorting instruments for chemical, biological, industrial and medical applications. Unfortunately, the performance of continuous microparticle isolation or so-called sorting is fundamentally limited by the trade-off between throughput, purity, and yield. For example, at a given throughput, high-purity sorting needs to sacrifice yield, or vice versa. This is due to Poisson statistics of events (i.e., microparticles, microparticle clusters, microparticle debris) in which the interval between successive events is stochastic and can be very short. Here we demonstrate an on-chip microparticle sorter with an ultrashort switching window in both time (10 µs) and space (10 µm) at a high flow speed of 1 m s-1, thereby overcoming the Poisson trade-off. This is made possible by using femtosecond laser pulses that can produce highly localized transient cavitation bubbles in a microchannel to kick target microparticles from an acoustically focused, densely aligned, bumper-to-bumper stream of microparticles. Our method is important for rare-microparticle sorting applications where both high purity and high yield are required to avoid missing rare microparticles.