Lossless information for Emerging Information Technologies

ongoing

In nanoelectronic circuits, interconnects use more energy than microprocessors, a situation clearly undesirable for e.g. autonomous Internet of Things applications based on charge and other information tokens. Overcoming this issue and minimising overall power consumption will be of paramount importance as we move towards Beyond-CMOS circuits. A novel approach is required. In LEIT I propose to investigate phonons as information carriers with typical ultralow energies of a fraction of a meV. As quanta of lattice vibrations, the high interactivity of phonons presents two key challenges: phonon-phonon scattering and losses in waveguides caused by interaction with e.g. lattice defects. I propose to overcome this by engineering phonon-phonon scattering in custom-designed phononic crystal-based structures moving towards narrow frequencies and non-interacting phonons at room temperature. These structures will exhibit a unique combination of features to allow phonon filtering, reflection and confinement, as well as transmission from one element (source) to another (modulator and waveguides), all of which will serve to direct and guide the phonon waves. Phonon losses will be minimised even eradicated by using topological phononic waveguides to transmit phonons over micrometre distances. The technological platforms will be made from silicon (Si) and Si-compatible materials, also incorporating transition metal dichalcogenides in order to reach the higher frequencies. In LEIT I will draw on my extensive experimental research on phonons in semiconductor nanostructures, Si membranes and phononic crystals to demonstrate the viability of acoustic phonons as low-energy information carriers. By doing so I will lay the scientific and technological foundations of a new phononics-based approach to information processing, offering a means of transmitting information that is extremely low-power and lossless, while also compact and integrable with Si-technologies.