Energy Filtering Non-Equilibrium Devices

Project Information

EFINED

Grant agreement ID: 766853

DOI

10.3030/766853

Project closed

EC signature date 8 August 2017

Start date 1 January 2018

End date 30 June 2022

Funded under

• EXCELLENT SCIENCE - Future and Emerging Technologies (FET)

Total cost

€ 2 919 037,50

EU contribution

€ 2 919 037,50

Coordinated by

TEKNOLOGIAN TUTKIMUSKESKUS VTT OY
Finland

Periodic Reporting for period 3 - EFINED (Energy Filtering Non-Equilibrium Devices)

Reporting period: 2020-01-01 to 2022-06-30

Summary of the context and overall objectives of the project

EFINED-project aims for revolutionary energy filtering nano-devices for information and communications technology (ICT). It is at the intersection of phononics, photonics, nanoscale electro-thermal devices and molecular engineering. By building new energy filtering devices down to molecular scales we aim to generate new knowledge and understanding of the electronic, phononic and near-field energy/heat fluxes at the fundamental limits of nano-scale energy management, and to demonstrate novel proof-of-concept non-equilibrium phonon engineered electro-thermal devices for real applications. The efficient nano-scale thermal management necessitates developing new theoretical and experimental tools for understanding and mastering the individual non-equilibrium energy/particle channels and inter-channel couplings. Control of the physical mechanisms behind non-equilibrium electronic energy filtering effects is addressed by bottom-up and top-down approaches. Bottom-up approach involves non-linear transport in molecular junctions where we develop new research tools that combine state-of-the-art molecular synthesis, thermal detectors, scanning probe microscopy technologies and theoretical modelling. In parallel with the molecular bottom-up approach our top-down approach focuses on scalable thermionic nano-junctions, which not only have great technological potential of their own, but also serve as a model system for the molecular devices. By employing non-linear out of equilibrium electro-thermal effects in molecular and scaled-down junction systems, we pursue the realization of proof-of-concept ICT devices utilizing these technologies within the time span of the project.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

In the first period of the project theoretical and numerical modelling efforts focused on evaluations of the different contributions (electronic, phononic, photonic) to the energy transfer at different length scales for both "top-down" and "bottom-up" configurations. Here a variety of key tools ranging from the Density Functional based Tight Binding (DFTB) technique at the molecular level to the Boltzmann transport equation and fluctuational electrodynamics at mesoscopic scale were utilized. The main results were identification of recipes for the engineering of the detrimental near-field heat transfer, predicting the electro-thermal performance of top-down elements and simulations of target molecules for bottom-up approach. On the experimental side a first demonstration of novel electronic cooling device utilizing the EFINED engineering concepts based on the top-down approach was successfully made. This is a key milestone indicating feasibility of the EFINED-approach of engineering different energy transfer channels at single junction. Molecular materials for the bottom-up approach were synthesized and tested electrically and thermally. The work comprises the development of measurement protocols to reach single molecule sensitivity. New instrumentation setups were designed targeting to measure the energy transfer effects on molecular scales (bottom-up). The setup construction and testing is currently on-going. The work related to the proof-of-concept (PoC) EFINED device application consisted of identifying potential application fields and EFINED technologies for the PoC application, investigating the related specifications and requirements, and designing conceptual devices for the selected application fields. The apparent main applications fields are photodetection and compact cooling. The cooling test platform utilizing the top-down thermionic junctions, the obtained experimental results and modelling (providing optimized designs) already pave the way for the PoC application.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

In order to reach our goals the project will proceed beyond the state of the art (SoA) in many areas of science and technology. Some key areas are:
-Single molecule electro-thermal measurements, where direct observation of non-linear electron induced cooling and quantification of non-linear efficiency is targeted
-Thermionic junction coolers and detectors, where utilization of phonon engineering is targeted in order to reach compact electronic refrigerator platforms and ultra-high sensitivity thermal detectors
-Near-field heat transfer theory (experiment), where we aim for unified fluctuational acoustodynamical theory (new platform that enables sub pW/K resolution)
-Molecular synthesis, where entirely new families of small molecules and cross-linked molecules tailored for electron filtering and phonon blocking are targeted.

The project is expected to have technological, scientific and socioeconomic impact in various fields, including thermal management and energy harvesting for ICT, IoT and IoE, photodetectors for ICT and instrumentation, methods and sensors for ultra-local and highly sensitive nano-device characterization, and electronic cooler platforms. The cooler platforms lead to impact also in the emerging field of quantum technologies where we are now witnessing large scale research and innovation actions and investments in the public and private sectors.

EFINED concept