These guys used an experiment called NuMI (NeUtrino beam at the Main Injector) to generate an intense beam of neutrinos. The beam consisted of about 25 pulses each separated by 2 seconds or so, with each pulse containing some 10^13 neutrinos.
The beam is pointed at a detector called MINERvA weighing about 170 tonnes and sitting in an underground cavern about a kilometre away. To reach MINERvA, the beam has to travel through 240 metres of solid rock.
MINERvA is one of world’s most sensitive neutrino detectors and yet, out of 10^13 neutrinos in each pulse, it detects only about 0.8 of them on average.
The FermiLab team used a simple on-off protocol to represent the 0s and 1s of digital code and transmitted the word “neutrino”.
The entire message took about 140 minutes to send at a data rate that these guys later worked out to be about 0.1 bits per second with an error rate of less than 1 per cent.
In general, long-distance communication using neutrinos will favor detectors optimized for identifying interactions in a larger mass of target material than is visible to MINERvA and beams that are more intense and with higher energy neutrinos than NuMI because the beam becomes narrower and the neutrino interaction rate increases with neutrino energy. Of particular interest are the largest detectors, e.g., IceCube that uses the Antarctic icepack to detect events, along with muon storage rings to produce directed neutrino beams.
In summary, we have used the Fermilab NuMI neutrino beam, together with
the MINERvA detector to provide a demonstration of the possibility for digital
communication using neutrinos. An overall data rate of about 0.1 Hz was realized,
with an error rate of less than 1% for transmission of neutrinos through a few
hundred meters of rock. This result illustrates the feasibility, but also shows the
significant improvements in neutrino beams and detectors required for practical applications.