Scientific work packages

Research SAWtrain will focus on three main research areas related to SAW-driven phononics, photonics, and electronics. The contribution from the SAWtrain members to each one of these areas is illustrated schematically in Figure 3.

The research activities within the areas are organized in the following three scientific work packages:

SAW-Tech: SAW Materials & Technology

(Coordination: TWENTE)

This work package will cover research on phononics and focus on materials and processing technologies for the generation of high-frequency SAWs on novel materials and structures (e.g. graphene, oxides, membranes, and SAW-based phononic crystals) as well as their integration with silicon CMOS technology. One of the goals is the development of very high-frequency SAW structures integrated with electronic devices for signal processing and sensing, as well as for the manipulation of photons, carriers, and spins in Si, graphene, and complex oxides. 

In particular, we will explore nano-imprint lithography for SAW frequencies above 20 GHz. We will also investigate novel concepts for SAW-based sensing elements as well as for the acoustic control of chemical reactions. This research area will also provide the technological basis for some of the advanced applications addressed in the fields of photonics and electronics.

Partners and secondments for WP1 (Down- and up arrows mean partner involved in out- and in-going secondments, respectively, associated with this research activity.)

ESR research projects

This WP will offer the six ESR projects listed in Figure 4, which also summarises the planned secondments. The ESRs in this WP will design and fabricate high-frequency SAW devices using nano-imprint lithography and other advanced cleanroom techniques.

The SAW devices will be used to realise acousto-electronic transport in Si-based structures (ESR5-TWENTE1), acousto-mechanical tuneable graphene (ESR1-PDI1), acousto-electronic transport in complex-oxide multilayers (ESR6-TWENTE2), integrated sensors based on Lamb waves (ESR7-CNR), acousto-photocatalysis (ESR8-UAU1) and high-Q 1D and 2D phononic cavities (ESR3-UVEG1).

SAW-PhoXon: SAW-driven hybrid nanophotonic and nanophononic structures

(Coordination: UAU)

The combination of photonics and phononics, termed PhoXonics, will lead to the exploitation of acoustic and optic resonators for the control of SAW and light quanta down to the single-particle level, which are expected to provide functionalities such as SAW-driven single-photon and single-phonon sources and detectors. Bulk acoustic fields are routinely used in optical devices, most prominently the acousto-optic modulator (AOM). To meet the requirements for future applications in advanced quantum optoelectronic devices, both the driving acoustic fields and the optical systems have to be adapted and improved.

We combine in WP2 activities to (i) confine and enhance acoustic fields in phononic resonators and to (ii) explore the interaction of these localised acoustic fields with photonic semiconducting or superconducting quantum two-level systems. This emerging class of phoXonic devices harness and transduce energy stored in electromagnetic fields and heat. These novel device concepts are envisioned to become a key enabling technology (KET) for future self-powered consumer products succeeding Photonics, which is a KET within Horizon 2020.

Partners and secondments for WP2 (Down- and up-arrows mean partner involved in out- and in-going secondments, respectively, associated with this research activity.

ESR research projects in WP2

This WP consists of the four ESR projects summarised in Figure 5. The ESRs in this work package will design and fabricate high-quality phononic cavity devices and use advanced cleanroom nanofabrication to deliberately couple the resonating acoustic fields to emerging electrically and optically active structures.

The latter includes high-quality solid-state quantum emitters, self-assembled quantum dots (QDs) (ESR9-UAU2), superconducting qubits (ESR15-CHALMERS), QDs in optical microcavities (ESR14-TREL), and integrated photonic devices (ESR4-UVEG2).

SAW-Transport: SAW-based quantum transport

(Coordinated by UCAM)

This research area is devoted to electronic functionalities related to the transport and manipulation of carriers and spins by moving SAW fields, with emphasis on carrier and spin control at the single-particle level for application in quantum information processing. Experimental work will be supported by theory.

Partners and secondments for WP3 (Down- and up-arrows mean partner involved in out- and in-going secondments, respectively, associated with this research activity.)

Single-electron control in solids is a driving force behind research in quantum physics with applications in quantum computing. Major challenges are the transport of a single electron from one functional part of a circuit to another in a very controlled way. Recent experiments at both CNRS and UCAM2 have transported a single electron from one QD to another using a SAW. One can similarly exploit the spin degree of freedom of a single electron. For that purpose, one requires narrow SAW transport channels as well as mechanisms for efficient generation and readout, e.g. using single-photon sources (SPSs). 

Likely advantages of these SPSs are the small jitter in the photon emission time and GHz repetition rates. Their fabrication is also compatible with conventional semiconductor technology.  This WP aims to implement such novel ideas to realise single-electron electronics and to use SAWs to process or transform quantum information carried by electrons and/or photons. It focuses on SAW-driven transport of single electrons, the control of their spins, and the readout of the spin by conversion to polarised single photons using high-repetition-rate SPSs. In addition, interaction of a moving SAW potential with graphene will be studied to develop plasmon launchers and electron pumps.

ESR research projects in WP3

The five projects are summarised in Figure 6. They provide ESRs with exciting training in SAW-related quantum-information phenomena including: integration of different functionalities for advanced SPSs based on single-carrier transport using quantum wires in microcavities (ESR2-PDI2), coupling electron and hole regions (ESR12-UCAM1), spin-qubit coupling mediated by dynamic QDs (ESR11-CNRS), and exploitation of new materials (e.g. graphene) for manipulation of single carriers and photons (ESR10-UPM). Experimentalists will interact with theorists modelling their devices (ESR13-UCAM2).