Imagine a safe that protects a precious gem from heat. Physicists have built a similar quantum 'memory cell' in three-dimensional space. It stores a qubit for an exponentially long time even at non-zero temperature by using clever repetition of simple protective layers. How long will your quantum information last in such a 'thermos'?
A quantum bit (qubit) is a delicate thing. Even a little heat destroys it, like a random nudge topples a crystal wine glass. To protect this fragile information, physicists have built a three-dimensional quantum structure resembling a Russian doll.
Inspired by the error-correction ideas of Shor and Preskill, the authors construct protection layer by layer. They take a simple energy landscape and gradually make it more complex, weaving in patterns of disorder (entropy) and order. Special stabilizers, named after Pauli, repel thermal disturbances. Thus, the qubit in the system’s ground state ends up securely hidden.
As a result, the information lifetime grows avalanchingly with each new layer — you can achieve storage longer than the age of the Universe. Usually, quantum states require cooling to near absolute zero, but here the protection works at realistic temperatures. This brings us closer to quantum chips without bulky refrigerators. A memory with stability comparable to a black hole challenges the standard model of decoherence.
🎯 At room temperature, quantum states usually decay in a split second. The new model promises a lifetime that grows avalanchingly with system size — theoretically longer than the age of the Universe.