Physics and Astronomy Colloquium

The Josephson junction is an ideal solid-state system for building "electrical atoms" that can function as quantum bits for a quantum computer. Recent advances in the materials and design of phase qubits have dramatically improved their coherence so that high-fidelity quantum logic operations can be performed. Combined with advances in microwave electronics, full characterization of single and coupled qubit logic gates are now possible using quantum tomography techniques. I will report on several recent experiments of our group demonstrating tomographic state measurement of single and coupled qubit logic gates that provides direct proof of entanglement. I will also discuss new experimental results where Fock states (photon number states) were generated in an electrical resonator.