Nanotechnology: A new era for photodetection?

Nowadays we live in the so-called "Silicon Era", in which devices based on the silicon technology permeate all aspects of our daily life. One can simply think how much silicon is in the everyday household objects, gadgets and appliances. The impact of silicon technology has been very relevant in photodetection as well. it enables designing large or very large-scale integration devices, in particular microchips and pixelled detectors like the Silicon Photo Multiplier made of micrometric channels grouped in mm(2) pixels. However, on the horizon, the recent development of nanotechnologies is opening a new direction in the design of sub-micron photodevices, owing to the capability to deal with individual molecules of compounds or to chemically grow various kinds of materials. Among them, carbon compounds appear to be the most promising materials being chemically very similar to silicon, abundant and easy to handle. In particular, carbon nanotubes (CNT) are a very intriguing new form of material, whose properties are being studied worldwide providing important results. The photoelectric effects observed on carbon nanotubes indicate the possibility to build photodetectors based on CNTs inducing many people to claim that we are at the beginning of a Post Silicon Era or of the Carbon Era. In this paper, we report on the most important achievements obtained on the application of nanotechnologies to photodetection and medical imaging, as well as to the development of radiation detectors for astro-particle physics experiments.