A superconducting qubit has transition frequency and is held at temperature in…
PHYSICS · Multi-part · Fermi University Physics · Quantum Mechanics · Quantum Information & Technology · Physical realizations and quantum technologies
Quantum Information and Technology, Ch Mixed states, generalised measurement and telling states apart
Problem
A superconducting qubit has transition frequency f=4GHz and is held at temperature T=40mK in thermal equilibrium, so its density operator is diagonal with populations set by the Boltzmann factor.
((a)) Compute hf/kBT.
((b)) Find the excited-state population p1.
((c)) Give the Bloch vector component rz and the purity of the state.