A glass chip, threaded with 128 optical waveguides, has been turned into a kind of quantum pinball machine. The role of balls is played by photons — quanta of light, and instead of mechanical flippers, microheaters control the routes, instantly altering the optical paths. The experimental task: launch up to four identical photons and record their final distribution at the output. This computational puzzle, known as boson sampling — the problem of calculating the distribution of indistinguishable bosons in a linear optical network, lies beyond the reach of classical computers and thus serves as a testing ground for demonstrating quantum supremacy.

The idea of boson sampling as a paradox capable of outsmarting supercomputers was put forward in 2011 by Scott Aaronson. The practical value of the implemented chip is enormous: the photon distribution captured by the Qolossus 3D — a three-dimensional photometry setup exhibits true randomness, unlike the pseudorandom algorithms of ordinary laptops. Such unpredictable randomness cannot be mathematically reproduced, making it an ideal resource for cryptographic encryption.

A striking feature of the device is that it operates without bulky cryogenic cooling systems: the quantum game runs at room temperature. Here, thermal motion is not a hindrance but, on the contrary, a tool that allows reconfiguring the waveguides using microheaters.