Figure 3.

Fidelity surface contours of the phase modulated π/2 (a) and π (b) pulses shown in Figure 1 with ‘relative resonance offset’ (ΔB/${\mathrm{B}}_1^0$) and relative rf strength (B₁/${\mathrm{B}}_1^0$). Inner contour represents a fidelity of 99%. c and d shows change in fidelity (%) with relative zz interaction strength (D / ${\mathrm{B}}_1^0$) π/2 and π pulses. Inner dotted line shows the response of single hard pulse of the same rf strength.