Research

To enable the emerging technologies, the new superconducting and photonic materials with a superior performance can be developed by manipulating the appropriate “elementary building blocks” through nanostructuring. Such “elementary blocks” are Cooper pair and fluxon for superconductivity and photon and plasmon for photonics/nanoplasmonics. This brings us to the main objectives of the proposed programme:

• to investigate the effect of the nanoscale confinement of the Cooper pairs and flux on superconductivity and flux behaviour in order to enhance the superconducting critical parameters (critical current, field and temperature), through nanostructuring thus enabling novel functionalities and new potential applications of the superconducting materials
• to investigate the optical confinement and plasmonic behaviour in individual nanocells (normal metallic, magnetic, superconducting, semiconducting and hybrid) and in metamaterials formed by the arrays of these nanocells for achieving new optical properties and for merging photonics with electronics at the nanoscale

Along the line of the main objective, the proposed research will be focused on the following topics:

• Evolution of superconductivity at nanoscale: optimizing the confinement of the Cooper pairs.
• Superconductivity and fluxon behaviour in hybrid nanosystems with tunable magnetic templates
• Confined flux in nanostructured single and two-component superconductors
• Vortex manipulation for developing fluxonics devices and superconducting elements for quantum computing
• Nanomodulated plasmonics structures (“photonic wire”) and photonic metamaterials
• Photonics of molecular magnets and quantum dots: photoluminescence, lasing and super-radiance
• Energy harvesting with plasmonics nanostructures for solar cells and other photonics application
• Optical and magnetic nano-markers for bio/med applications

Theoretical modeling will play an essential role in this proposal since the confinement of the condensate and light inside the nanostructured samples can be successfully treated in the framework of the Ginzburg-Landau (and/or Bogolyubov-De Gennes) equations for superconductivity and the Maxwell (and/or time dependent Schrodinger) equations for photonics, with the imposed proper boundary conditions at the nanofabricated boundaries.

The continuing development of powerful nanofabrication techniques, combining optical and e-beam lithography (INPAC+collaboration with IMEC) with electro-chemical growth and self-assembly (collaboration with MTM and LLN) creates adequate facilities for the design and the implementation of the superconducting and photonics materials with the superior performance needed for the emerging new technologies. For the interdisciplinary experimental studies a variety of the techniques available at the K.U. Leuven Center of Excellence INPAC will be used. Moreover, the modern local imaging set-ups with the nanoscale resolution will play a crucial role:: a key success factor here is the possibility to map the important relevant parameters (local density of the Cooper pairs, magnetic field and optical intensity) with the nanoscale resolution for different confinement patterns in a variety of the nanoengineered samples to be studied in the framework of this proposal.