Giuseppe Marra | research scientist
National Physical Laboratory

Giuseppe Marra is a Principal Research Scientist in the Time and Frequency group at the National Physical
Laboratory in the UK. His primary research interest is in the dissemination of ultra-stable optical signals
over continental and intercontinental optical fibre links, with focus on those derived from state-of-the-art
optical atomic clocks.
He has pioneered ultra-stable interferometric techniques over telecommunications seafloor cables for the
detection of environmental signals, such as earthquakes, ocean currents, tides and other ocean signals.
Recently he has developed an innovative technique that enables to use existing seafloor cables as arrays of
environmental sensors without modifications to the subsea infrastructure.
He is also actively working on advancing the research on optical fibre link-based suitable frequency
transfer techniques for the comparison of state-of-the-art optical atomic clocks located in different
continents, towards the development of next-generation global timescales.