Teaching phonons to be photons and electrons

The operation principle of electronic devices is the control, in a broad sense, of the flow of charge carriers through a channel whose conductivity can be tuned by means of doping and applying an external bias. Nature, nonetheless, offers different alternatives to transfer energy, thus information. Heat, the most pervasive and ubiquitous form of energy, is one of them. Although it is normally regarded as wasted energy, due to its elusive nature when it comes to control it, there are no fundamental reasons why devices that work with the heat flux and that rely on the same principles of electronic devices cannot be envisaged. This is the realm of phononics [1], the discipline that investigates the manipulation of heat and that aims at engineering devices with the same functionalities than their electrical counterparts.

In this talk I will discuss possible strategies to implement phononic devices, focusing on the insight provided by theoretical modeling and numerical simulations. A few selected case studies will be analyzed, showing how the flexibility provided by state-of-the-art growth techniques of nanowires [2] could help designing materials with a tailor-made thermal conductivity, exploiting degrees of freedom such as the diameter [3], the composition [4,5] or the crystal phase[6,7]. The design and the engineering of building blocks of a phonon toolbox, such as thermal diodes [3], thermal switches and phonon polarizers [8], will also be discussed..

Seminar, July 10, 2018, 12:00. ICFO s Seminar Room

Hosted by Prof. Adrian Bachtold