From left to right: Matt Peloso, Alessandro Restelli (NIST), Christian Kurtsiefer, Antia Lamas-Linares, Ilja Gerhard and Caleb Ho at the Grand Canyon with the entanglement source & the sending telescope.
A team from the quantum optics group recently took their quantum key distribution system quite literally into the "wilderness". It started with an invitation from our friends at NIST to do a joint exhibition of QKD systems at the two largest computer security (a.k.a. hackers) conferences in the world: Black Hat (for the corporate types) and DEFCON (for the alternative version) in Las Vegas. The CQT team had done this before in the European hacking scene (24c3) so it was possible. The decision to go ahead generated a flurry of activity to get the system ready, packaged, and sent, as well as some modifications for an additional crazy idea ...
On the 4th of August Antia and Christian set out for Vegas from Singapore, while Ilja flew from Zurich. We all met at Caesar's Palace and found out that our equipment had been retained in customs for "fumigation". The day before the conference, our equipment finally arrives. We need to make sure it survived, realign all the optics, and get all the bits and pieces to work together, including the new stars of the show, a pair of OLPCs which will run the whole protocol. At 4:30 am, just a few hours before the conference attendees flow into the exhibition floor, the system is finally ready and producing quantum generated key at Black Hat!
Two full days of explanations later, it is time to pack up and move to a different hotel. We are now going for DEFCON, the real hackers conference. No photos of people are allowed and the conference badge is a printed circuit board ... need I say more? Another crazy night of setting up, but again, the equipment survives the move. Two more days of explanations with little sleep follow. In the mean time Christian flies off to give a lecture in Waterloo (Canada); fittingly it is about "Practical Quantum Cryptography". Ilja and Antia pack up and move the equipment to yet another hotel for the last leg of the adventure.
As it turns out Las Vegas is near grand Canyon, and what a better place to prove that QKD can be done anywhere, and that entanglement sources can be robust? We buy camping supplies and lots of batteries and contact again the people from the National Park Service at Grand Canyon. Our little "addition" to the hackers conference can go ahead. Alessandro from the NIST team joins us and Caleb and Matt fly in from Waterloo where they were attending the workshop on quantum crypto. We hire two cars and off we go for the Grand Canyon.
We set up initially on the south rim of the Grand Canyon on two places separated by around 3km. The place is spectacular and the setup phase goes smoothly among the amused looks of the tourists. The first night we manage to see coincidences between the two sides and leave it for the next day to make further progress. As it turns out, this is as far as we got. Two detectors broke and our field fix allowed us for one more try ... but the weather gods were not with us and a huge electrical storm broke on top of the testing sites. We waited in vain for it to pass, but it was not to be, it was the last night at the canyon. We found out later that it was a major storm that broke a damm and forced the evacuation of several hundred people ... but by then we were on a plane headed back to Singapore. We learned a lot from the trip; our equipment worked flawlessly from batteries, the modified astronomical telescope worked for receiving the photons and while the key was not exchanged, it is for sure within our reach for the next attempt.
SPECIAL THANKS: To Carl Bowman from the National Park Service for helping with site selection and all the friendly advice.