As discussed in Section Error! Reference source not found., a large ω $& and low 𝜔̇, to maximize Q, are preferred to optimize the efficiency of chirped DNP. Therefore, 12 µs pulses (the maximum allowed by the EIK) were used for all experiments in order to minimize 𝜔̇. In addition, to increase the DNP enhancement, we set the magnetic field to match the SE condition at 93.7 GHz frequency where the EIK produces the optimal power (∼250 W, ω $& /2π ∼ 20 MHz, see Fig. ). A train of NMR saturating pulses was applied to dephase the nuclear spin polarization prior to each DNP build-up, and a solid echo 1 H experiment was used to monitor the DNP enhanced NMR signal. Shown in Fig. is the DNP Zeeman field profile recorded for 10 mM trityl-OX063 at 70 K using the ASE under optimized conditions. The enhancements were recorded using a 12 µs, 40MHz frequency chirp with a repetition delay of 1.2 ms. For the data in Fig. the chirps were performed for a total of 150 s. These results are compared to the SE Zeeman field profile recorded without chirping. In addition, the relative microwave power profile of the EIK is included in the figure as the dashed line. The echo detected EPR spectrum is shown in the Supporting Information. The ZQ SE/ASE enhancement at 93.98 GHz is significantly smaller than the DQ enhancement due to the lower 𝜔 $& at the high frequency.