Hardware & Errors
Superconducting Qubit
A qubit implemented using tiny superconducting electrical circuits cooled to near absolute zero.
Definition
Superconducting qubits encode quantum information in the behavior of electrical current in specially designed circuits made from superconducting materials, which must be cooled to extremely low temperatures (near absolute zero) to exhibit their quantum properties.
Technical Definition
The most common type, the transmon qubit, uses a Josephson junction (a thin insulating barrier between two superconductors) to create the nonlinear behavior needed to isolate two specific energy levels representing |0⟩ and |1⟩.
Visual Explanation: An Analogy
Think of a superconducting qubit like a tiny, precisely tuned electrical circuit that behaves according to quantum rules only when cooled to temperatures colder than outer space — similar to how some materials only become superconducting (carry electricity with zero resistance) at extremely low temperatures.
Real-World Use Cases
- The most widely used qubit technology today, used by IBM, Google, and Rigetti
- Benefits from manufacturing techniques similar to existing semiconductor chip fabrication
- Generally offers faster gate operation speeds than trapped-ion systems, at the cost of shorter coherence times