From nuclear to meso systems: how small is simple and how large is complex?

Abstract

Abstract. The question is asked: what are new size-dependent effects characteristic of the nanoscale range which justify considering 'dynamics on the nanoscale' as a scientific area in its own right rather than merely an extension of existing knowledge to a different parameter range. A preliminary list of such effects is drawn up. It is shown to include many challenging unsolved problems as well as a number of fundamental investigations which are more or less advanced in development at the present time.

Dynamics of systems on the nanoscale

“…Contribution [28] to this Topical Issue reflects the spirit and the atmosphere of this Session. It seeks for the answer to a seemingly simple question: what are new sizedependent effects characteristic of the nanoscale range which justify considering dynamics on the nanoscale' as a scientific area in its own right rather than merely an extension of existing knowledge to a different parameter range.…”

Microscopyc description of the Photothermal increase of temperature for metallic nanoparticles excited with short-laser pulses

“…Conversely, for NP's with radii larger than 42 nm, the statistical analysis predict lower values than these using macroscopic variables. Noticeably, the models disagreement, in terms of particle size and induced PT magnitude, seems to follow a match with the Mie limit, along with a strong dependency with the frequency bath in which the system is placed [2,3].…”

“…These conditions combine the strong confinement of Mie resonant and nonresonant absorbed electromagnetic field, which then gra-dually decays through ohmic losses, the type of collisional processes fueling non-radiative decays; i.e. Joule heating [1][2][3][4][5].…”

“…However, when the source of illumination are short laser pulses (∼ ns), interacting with metallic nanoparticles in the Mie regime (r 0 ≤ 50nm), the macroscopic temperature description is at the borderline of the thermodynamic limit [2,12,13]. Therefore since ∆T , is described in terms of macroscopic parameters, thus it is suggestive that it requires to be re-casted to obtain an expression in which the micro-or rather nanoscale, can be better described.…”

“…In other words, how can the classical temperature be properly defined for a system verging on the microscopic? In part these questions are broadly reviewed in [2], while they were the subject of discussion in [12] and [15]. In [12], the authors managed to describe how a system obeying statistical mechanics leads to proper macroscopic thermodynamics (scale-up).…”