Project description DEENESFRITPL A Josephson junction-based spectrometer targets mesoscopic systems Mesoscopic systems are those that are larger than a few atoms or molecules but smaller than the everyday objects we can see and touch. They serve as an interesting testbed for studying the interface between quantum mechanics and macroscopic systems. Mesoscopic devices, which preserve quantum coherence over lengths larger than the atomic scale, offer a unique opportunity to both engineer and investigate excitations at the single quanta level. However, current spectroscopic methods do not enable one to probe mesoscopic systems with radiation and detect their small absorption signals. The European Research Council-funded JSPEC project will develop an on-chip, Josephson junction-based spectrometer ideally suited for probing elementary excitations in mesoscopic systems. Show the project objective Hide the project objective Objective Spectroscopy is a powerful tool to probe matter. By measuring the spectrum of elementary excitations, one reveals the symmetries and interactions inherent in a physical system. Mesoscopic devices, which preserve quantum coherence over lengths larger than the atomic scale, offer a unique possibility to both engineer and investigate excitations at the single quanta level. Unfortunately, conventional spectroscopy techniques are inadequate for coupling radiation to mesoscopic systems and detecting their small absorption signals. I propose an on-chip, Josephson-junction based spectrometer which surpasses state-of-the-art instruments and is ideally suited for probing elementary excitations in mesoscopic systems. It has an original design providing uniform wideband coupling from 2-2000 GHz, low background noise, high sensitivity, and narrow linewidth.I describe the operating principle and design of the spectrometer, show preliminary results demonstrating proof-of-concept, and outline three experiments which exploit the spectrometer to address important issues in condensed matter physics. The experiments are: measuring the lifetime of single quasiparticle and excited Cooper pair states in superconductors, a topic relevant for quantum information processing; determining whether graphene has a bandgap, a fundamental yet unresolved question; and recording a clear spectroscopic signature of Majorana bound states in topological superconductor weak links.Various applications of the superconducting circuits developed for the spectrometer include a Josephson vector network analyzer, a cryogenic mixer, a THz camera, a detector for radioastronomy, and a scanning microwave impedance microscope. In itself the proposed JJ spectrometer is a general purpose tool that will benefit researchers studying mesoscopic systems. Ultimately, Josephson junction spectroscopy should not only be useful to detect existing elementary excitations but also to discover new ones. Fields of science natural sciencesphysical sciencesopticsmicroscopynatural sciencesphysical sciencescondensed matter physicsmesoscopic physicsnatural sciencesphysical sciencesastronomyphysical cosmologynatural sciencesphysical scienceselectromagnetism and electronicssuperconductivitynatural sciencesphysical sciencesopticsspectroscopy Programme(s) H2020-EU.1.1. - EXCELLENT SCIENCE - European Research Council (ERC) Main Programme Topic(s) ERC-StG-2014 - ERC Starting Grant Call for proposal ERC-2014-STG See other projects for this call Funding Scheme ERC-STG - Starting Grant Host institution COLLEGE DE FRANCE Net EU contribution € 1 651 232,50 Address PLACE MARCELIN BERTHELOT 11 75005 Paris France See on map Region Ile-de-France Ile-de-France Paris Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Total cost € 1 997 497,50 Beneficiaries (2) Sort alphabetically Sort by Net EU contribution Expand all Collapse all COLLEGE DE FRANCE France Net EU contribution € 1 651 232,50 Address PLACE MARCELIN BERTHELOT 11 75005 Paris See on map Region Ile-de-France Ile-de-France Paris Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Total cost € 1 997 497,50 Third-party Legal entity other than a subcontractor which is affiliated or legally linked to a participant. The entity carries out work under the conditions laid down in the Grant Agreement, supplies goods or provides services for the action, but did not sign the Grant Agreement. A third party abides by the rules applicable to its related participant under the Grant Agreement with regard to eligibility of costs and control of expenditure. CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS France Net EU contribution € 346 265,00 Address RUE MICHEL ANGE 3 75794 Paris See on map Region Ile-de-France Ile-de-France Paris Activity type Research Organisations Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Total cost € 346 265,00