Quantum technology is usually associated with ultra-cold environments and rigid materials like silicon or diamond. But researchers have now achieved a remarkable breakthrough—the creation of a biological quantum bit (qubit) from a fluorescent protein. Unlike conventional qubits, this one is at home in the watery, complex world of biology.
According to a study published August 20 in Nature, the qubit is only about 3 nanometers wide. Scientists activated its quantum behavior by shining laser light, applying microwaves, and analyzing its glow. The result: a functioning qubit inside a living system.
Qubits differ from classical computer bits because they can exist as both 0 and 1 simultaneously, a property known as quantum superposition. Instead of adapting traditional qubits to biology, physicist David Awschalom of the University of Chicago explains the team’s approach: “Maybe you should turn the problem inside out … a quantum bit that would be very happily ensconced in another biological entity.”
The qubit originates from the fluorophore, the light-emitting part of the protein. This region has a property called spin, which can be manipulated to function as a quantum state. The team demonstrated Rabi oscillations, a clear signature of qubit behavior, in both human cells at 175 Kelvin (–98 °C) and in E. coli bacteria at room temperature.
What makes this protein qubit special is its protective molecular shell, shielding it from environmental interference. As study coauthor Peter Maurer notes, “Fluorescent proteins in general have the advantage that the fluorophore … is in this protective shell.”
Although promising, experts remain cautious. Biophysicist Romana Schirhagl warns that these qubits may struggle to remain bright enough for reliable use in real biological settings. Still, this innovation hints at a future where quantum sensors measure magnetic fields and temperatures inside living cells, potentially revolutionizing medical imaging and diagnostics.
Quantum Biology Breakthrough: Protein Qubits Work at Room Temperature
