Dynamical decoupling
Control pulses reverse accumulated unwanted phase while retaining selected signals.
$$y(t)\in\{-1,+1\}$$
Physical intuition
Control pulses reverse accumulated unwanted phase while retaining selected signals.
Deep dive: physical mechanism
Pi pulses toggle the sign of longitudinal coupling; the resulting filter function suppresses slow noise or targets AC fields.
What is measured experimentally?
Echo contrast and resonance dips reveal noise bands.
Assumptions, noise and limitations
Pulse errors and finite duration can spoil ideal cancellation.
Research and simulation exercise
Compute the filter function of Hahn echo and CPMG.
Connect the ideas
Explore the chapter overview, learning path, and references.