A regular computer amplifies a signal like a megaphone amplifies a voice. But a megaphone doesn't work for a quantum computer: it distorts the whisper too much. And the whisper here is the signal from qubits, the cells of quantum memory. The signal is so weak that any extra noise drowns it out.
What's needed is an amplifier that works at liquid helium temperatures — around -270 degrees Celsius. And one that adds no more noise to the signal than nature allows. Such amplifiers already exist, but they are assembled by hand, like watches. That's slow and expensive.
Now, the amplifier has been printed on a standard chip production line — the same one that makes processors for phones. The device is the size of a grain of rice. It amplifies signals from 3 to 11 gigahertz, as if a megaphone worked equally well for bass and flute.
The main achievement is precision. All amplifier components match to within one percent. So the device works reliably, without surprises. This is the first step toward assembling quantum computers on a conveyor belt, like regular ones.
The amplifier operates at -270°C. At that temperature, even air becomes liquid.