Controlling Light, Heat, and Vibrations in Plasmonics and Phononics

Abstract

more than a 100 years to the beginning of the twentieth century. [1] However, owing to the recent improvements in nanofabrication and characterization techniques, it was only in the last decades that plasmonics emerged as a prolific area of applied optics. Phononics is the field of condensed matter physics that studies collective vibrational modes of matter (phonons) as means to carry energy (heat) and information (vibration and sound). Beginning with atomic scale models describing the lattice dynamics, its theoretical roots go back to the foundations of the field of condensed matter physics itself before the first half of the twentieth century [2,3]. Analogously to plasmonics, the ability to fabricate structures with subm µ features is now opening possibilities for exploiting phonon propagation hence promoting a renewed interest in the phononic field. Even more importantly, the nowadays advanced micro-and nano-fabrication technology enables the actual realization of opto-thermo-mechanical nanodevices [4,5] where the interaction between photons, electrons, and phonons can be properly investigated and exploited. Starting from the seminal work of Ritchie in 1957, [6] numerous studies have been performed on systems supporting plasmonic effects, such as metallic slits or perforated metallic films together with hybrid structures formed by metal and dielectric. [7] Plasmonic nanostructures have especially attracted a lot of attention for their ability to couple with light whose Plasmonic nanostructures have attracted considerable attention for their ability to couple with light and provide strong electromagnetic energy confinement at subwavelength dimensions. The absorbed portion of the captured electromagnetic energy can lead to significant heating of both the nanostructure and its surroundings, resulting in a rich set of nanoscale thermal processes that defines the subfield of thermoplasmonics with applications ranging from nanochemistry and nanobiology to optoelectronics. Recently, phononic nanostructures have started to attract attention as a platform for manipulation of phonons, enabling control over heat propagation and/or mechanical vibrations. The complex interaction phenomena between photons, electrons, and phonons require appropriate modelling strategies to design nanodevices that simultaneously explore and exploit the optical, thermal, and mechanical degrees of freedom. Examples of such devices are micro-and nanoscale opto-thermomechanical systems for sensing, imaging, energy conversion, and harvesting applications. Here, an overview of the fundamental theory and concepts crucial to the modelling of plasmo-phonon devices is provided. Particular attention is given to micro-and nanoscale modelling frameworks, highlighting their validity ranges and the experimental works that contributed to their validation and led to compelling applications. Finally, an open-ended outlook focused on emerging applications at the intersection between plasmonics and phononics is presented.

Going Above and Beyond: A Tenfold Gain in the Performance of Luminescence Thermometers Joining Multiparametric Sensing and Multiple Regression

“…In nanomedicine, for example, the accurate determination of the temperature can yield the development of new thermal diagnosis and therapy methods, [8,11,34] whereas in micro or nanoelectronics tracking the thermal exchanges at submicrometric length scales can afford a detailed understanding of the thermal properties in spatial domains for which the macroscopic transfer laws are not valid anymore. [35] In fact, real-world applications of luminescence thermometry are hindered by the accuracy of the nanothermometers, which is given by the temperature uncertainty, 𝛿T = 1 S r 𝛿Δ Δ , [7] where 𝛿Δ/Δ is the relative uncertainty in Δ, determined by the detection system used. The best 𝛿T value reported by now was achieved by using lanthanide-bearing nanomaterials, with 𝛿T ranging between 0.1 and 0.3 K. [4,20] Nowadays, cutting-edge reports on luminescence nanothermometry are reaching the boundary of the accuracy of the nanothermometers.…”

Plasmomechanical Systems: Principles and Applications

“…Indeed, the resonant excitation of surface plasmons in subwavelength noble metallic nanostructures gives rise to strong field enhancements in proximity of the nanostructures. These generated electromagnetic hot spots can be exploited as nanoscale heat sources [93][94][95] for low-power photothermal probing. [83,96] Generally, thermomechanical detectors rely on the structural deformation upon exposure to radiation.…”

Plasmonic Nanoarchitectures for Single‐Molecule Explorations: An Overview

“…Such fundamental studies on the optomechanical coupling at the atomic level have inspired similar research at the nanoscale. [96] The marriage of plasmonic resonance and mechanical vibration at the nanometer scale has led to the emergence of a new field of study called plasmomechanics, which explores the interaction between light and plasmomechanical nanoresonators and related phenomena. [97]…”