Superconducting Qubits

Currently, superconducting qubits are the most widely used candidates for quantum computing systems. These consist of an insulator (typically Aluminum oxide, AlOx) sandwiched between two layers of superconductors (typically Aluminum) , known as the Josephson Junction. These behave as anharmonic oscillators and can be manipulated by using radio frequency pulses. Some of the kinds of superconducting qubits include charge qubits, flux qubits etc. Also these qubits can be fixed frequency or frequency tunable qubits. The main obstacle to scaling these systems of superconducting qubits is to obtain high fidelity quantum gates on these larger systems. We use open-loop optimal control techniques for control, characterization and calibration of different kinds of superconducting qubits to obtain optimal gate fidelities.