  Hyperfine atomic states are among the most promising candidates for qubit
encoding in quantum information processing. In atomic systems, hyperfine
transitions are typically driven through a two-photon Raman process by a laser
field which is amplitude modulated at the hyperfine qubit frequency. Here, we
introduce a new method for generating amplitude modulation by phase modulating
a laser and reflecting it from a highly dispersive optical element known as a
chirped Bragg grating (CBG). This approach is passively stable, offers high
efficiency, and is compatible with high-power laser sources, enabling large
Rabi frequencies and improved quantum coherence. We benchmark this new approach
by globally driving an array of $\sim 300$ neutral $^{87}$Rb atomic qubits
trapped in optical tweezers, and obtain Rabi frequencies of 2 MHz with
photon-scattering error rates of $< 2 \times 10^{-4}$ per $\pi$-pulse. This
robust approach can be directly integrated with local addressing optics in both
neutral atom and trapped ion systems to facilitate high-fidelity single-qubit
operations for quantum information processing.
