The behavior of the ground-state hyperfine coherence formed in coherent population trapping (CPT) is studied. Using potassium atoms cooled with a magneto-optical trap, a pure hyperfine CPT state was prepared in a magnetic field, and hyperfine coherent effects in an open system were experimentally studied with off-Raman resonance oscillations (ORRO). Comparisons were made to full numerical simulations and to a pseudo-three-level model. The frequency and phase of ORRO can be manipulated by changing the relative frequency and phase of the lasers.
The behavior of the ground-state hyperfine coherence formed in coherent population trapping (CPT) is studied. Using potassium atoms cooled with a magneto-optical trap, a pure hyperfine CPT state was prepared in a magnetic field, and hyperfine coherent effects in an open system were experimentally studied with off-Raman resonance oscillations (ORRO). Comparisons were made to full numerical simulations and to a pseudo-three-level model. The frequency and phase of ORRO can be manipulated by changing the relative frequency and phase of the lasers.