Zardo, Ilaria
Date: Wednesday, April 11, 2018
Time: 14:00
Place: ETH Zurich, Hönggerberg, HPF G 6
Host: Giacomo Scalari
Phonon engineering and manipulation with nanowires
Ilaria Zardo
Department of Physics, University of Basel
In the last decades, the capability to control photons and electrons paved the way for extraordinary technological developments in electronic and optoelectronic applications. A similar degree of control is still lacking with quantized lattice vibrations, i.e. phonons. The manipulation of phonons is a challenging objective, which holds the promise of a step forward in the exploitation of quantum physics and implies the manipulation of sound and heat.1 The understanding and ability to manipulate phonons as quantum particles in solids enable the control of coherent phonon transport, which is of fundamental interest and could also be exploited in applications.1,2 The recently growing research field called “Nanophononics” deals with the investigation and control of vibrations in solids at the nanoscale.3 As an example, logical operations using phonons to switch, amplify and route signals can be realized by nanoscaling.
In this talk, we discuss nanowires (NWs) as powerful building-blocks for phononic applications.
The concept of phonon engineering in NWs is exploited in twin superlattice (SL) GaP NWs. We experimentally show that a controlled design of the NW phononic properties can be decided à la carte by tuning the SL period. These results represent the first experimental demonstration of phonon engineering in NWs and are an important step in the investigation of the quantum-mechanical nature of phonons.
Furthermore, we present the realization of a NW-based thermal diode as a key element of phononic integrated circuits. Namely, the thermally rectifying behavior is explored in semiconductor NWs with a sudden change in diameter, referred to as “telescopic NWs”.4
References:
[1] M. Maldovan, Nature 503, 209 (2013); M. Maldovan, Nature Materials 14, 667 (2015).
[2] S. Voltz et al. Eur. Phys. J. B 89, 15 (2016).
[3] A. A. Balandin and D. L. Nika, Materials Today 15 (6), 266 (2012).
[4] X. Cartoixà, L. Colombo, and R. Rurali, Nano Letters, 15 (12), 8255-8259 (2015)