Phase‐Responsive Fourier Nanotransducers for Probing 2D Materials and Functional Interfaces

Abstract

Light scattered by an object contains plethora information about the object which is distributed evenly among all possible Fourier components of light observed in the far-field. There are some cases, however, where this information is accumulated in the light confined by the object and then encoded in just a few coherent optical beams. Here, Fourier nanotransducers based on 2D plasmonic metamaterials are introduced, which are capable of confining light in 2D plane contacting with a functional interface, gathering information about its properties, and then transmitting the information into discrete optical beams with amplified phase relations. It is shown that phase of light in such beams can be used for probing dynamic physical properties of 2D materials and performing bio/chemical sensing with unprecedented sensitivity. Using a Fourier transducer based on periodic gold nanostructures, ferroelectric response from a single atomic layer of MoS 2 is resolved and studied for the first time, as well as the detection of important antibiotic chloramphenicol at fg mL −1 level is demonstrated, which several orders of magnitude better than reported in the literature. The implementation of phase-responsive Fourier nanotransducers opens new avenues in exploration of emergent 2D structures and radical improvement of biosensing technology. nanostructured metasurfaces providing new laws of reflection and refraction as well as designer beam shapers. [5,6] Systematic studies of light phase changes in space domain have a long successful history and resulted in several breakthrough technologies, such as holography [7] and phase contrast. [8] Changes of light phase under evolution of a nanomaterial with time attracted significantly less attention. This seems to be surprising as behavior of light phase in time domain was paramount for detection of faint signals associated with gravitational waves [9] and important for development of compact and fast phase light modulators [10] among others important advancements.Nanotransducers enabling manipulations of light phase in 2D plane are of particular importance as they could provide breakthrough tools for studying properties of planar structures and functional interfaces, including newly emerging 2D materials and van der Waals heterostructures [11] that promise appealing applications in electronics, optics, photochemistry, biomedicine, etc. The optical response of 2D materials was extensively used for elucidating their physical properties; however, currently available methods (absorption spectroscopy, Raman, photoluminescence) provide mostly basic information and have obstacles in gathering dynamic Sensors/Biosensors

Layered material platform for surface plasmon resonance biosensing

“…The phase change (~8.9 degrees) after testing on 1 pg/mL HT-2 reveals an ultrasensitive detection limit ~0.5 fg/mL for an experimental ellipsometer phase resolution ~0.05 degrees. (The improvement over conventional amplitude sensitivity comes about from the darkness of SLG protected Cu resonances and enhanced stability of phase measurements 48,49 ). This limit could be pushed down to ~0.1 fg/mL in a dedicated phase setup capable of a phase resolution of 0.01 degrees 50 , 1000 times more sensitive than amplitude measurements.…”

Topological phase singularities in atomically thin high-refractive-index materials

“…Simple planar structures studied here are easy to incorporate and leverage in industrial and scientific devices where the optical phase plays a critical role. 5,24,25,31,44 The most prominent practical examples are holography, 24,25,44 image processing 45,46 , label-free bio-or chemical sensing, [47][48][49][50] and quantum key distribution. 51,52 To validate the concept, we demonstrated that the liquid/PdSe 2 /SiO 2 /Si system is already an ultrahigh sensitive sensor owing to rapid phase change around the topological point.…”

PLGA Nanoparticles Decorated with Anti-HER2 Affibody for Targeted Delivery and Photoinduced Cell Death

“…The development of new, and the improvement of existing methods of diagnostics and therapy of oncological diseases is impossible without the involvement of new non-standard tools in biology and biomedicine [ 1 , 2 ]. Nanoparticles of various natures have a wide range of properties that are not inherent in bulk samples or small molecules, thus making it possible to solve the most pressing problems both in therapy and in the diagnosis of diseases [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ].…”