We present a biophotonics platform based on the optical manipulation of photonic membranes via holographical tweezers. We review the fabrication and manipulation protocol which grants full six-degrees-of-freedom control over these membranes. This is despite the membranes having extreme aspect ratios, being 90 nm in thickness and 15 - 20 μm in side length. The photonic properties of the trapped membranes can be tailored to very specific applications, by structuring their topology carefully. Our method merges the flexibility of photonic design of optical meta-surfaces with the advanced manipulation capability offered by holographic optical tweezers. Here we demonstrate the validity of our approach, discussing the peculiar mechanical properties of trapped photonic membranes. Specifically, we focus on imaging and surface-enhanced Raman spectroscopy applications.
Photonic membranes (PMs) are thin, highly-flexible, membranes which can be imbued with specific photonic functionalities when used to play host to plasmonic features.1–3 PMs can then take that photonic functionality and transfer it to an external object, provided that they can be manipulated with enough precision. We demonstrate a fabrication and optical manipulation protocol that allows PMs to be manoeuvred through a microfluidic environment, and show that the trap stiffness of such a scheme is on par with current techniques. The PMs shown here are 90 nm thick, with the potential to be extremely flexible. We comment on their current deformability.
Flexible metamaterials (FMMs) at optical frequencies can conform to a wide range of target geometries whilst allowing their optical properties to be tuned post-fabrication. Here we discuss this potential by presenting our recent and preliminary results, obtained for FMMs at visible frequencies for sensing, filtering and imaging applications.
In this paper we present the design and applications of flexible photonic membranes. We discuss their use as versatile photonic layers in the framework of lab-on-fibre applications, specifically focusing on the design of angular robust spectral filters. We also show alternative routes to their fabrication, highlighting the opportunities and limitations associated to each approach. Finally we present our preliminary results on the all-optical control over flexible membranes, as a potential method to fine-tune their opto-mechanical properties to the required application.