Two-qubit gates via exchange
Exchange can entangle neighboring spin qubits.
$$U_{\rm ex}(t)=e^{-iJt\mathbf S_1\cdot\mathbf S_2/\hbar}$$
Physical intuition
Exchange can entangle neighboring spin qubits.
Deep dive: physical mechanism
Pulsed tunnel barriers control J and implement exchange-family gates.
What is measured experimentally?
Conditional oscillations and randomized benchmarking assess operation.
Assumptions, noise and limitations
Residual coupling, leakage and pulse distortion limit fidelity.
Research and simulation exercise
Construct a two-spin unitary and evaluate entanglement.
Connect the ideas
Explore the chapter overview, learning path, and references.