In yet another step toward the realization of a practical quantum computer, scientists working at Princeton and the Joint Quantum Institute (JQI) have shown how a major hurdle in transferring information from one quantum bit, or qubit, to another might be overcome. Their so-called “quantum bus” provides the link that would enable quantum processors to perform complex computations.

The JQI is a collaborative institute of the National Institute of Standards and Technology (NIST) and the University of Maryland College Park.

Qubits are unlike a classical bit because they can be not only a 1 or 0 but also both, simultaneously. This property of qubits, called superposition, helps give quantum computers a tremendous advantage over conventional computers when doing certain types of calculations. But these quantum states are fragile and short-lived, which makes designing ways for them to perform basic functions, such as getting qubits to talk to one another—or “coupling”—difficult.

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