Study of resonance fluorescence in cadmium: Modulation effects and lifetime measurements

Polarization entanglement and quantum beats of photon pairs from four-wave mixing in a cold87Rb ensemble

“…Consequently, the energy difference between photons from the two paths leads to a modulation of the time correlation function between signal and idler photodetection, as shown in figure 4. This, and other similar phenomena, is known as quantum beats: it was predicted at an early stage of quantum physics [29], and first experimentally observed in pulsed optical excitation of atoms with two upper states decaying to the same ground state [30,31]. Quantum beats have also been observed in cascade decay systems of dilute atomic vapours [32], dense thermal atomic vapours [33], and for single ions [34].…”

Spontaneous creation and persistence of ground-state coherence in a resonantly driven intracavity atomic ensemble

“…It begins at τ = 0 from approximately 0.46, which shows that immediately after the photon is detected the atom is to a good approximation in the superposition |ψ 0 ; p 0 ≈ 1 in Eq. (6).…”

“…A time-domain analogue of double-slit interference can occur inside multi-level atoms, where photon emission via parallel transitions can result in a modulation of the emission intensity at the frequency of a level splitting-the phenomenon of "quantum beats" (see, e.g., [5,6]). A distinction has traditionally been drawn between "Type-I" or "V" atomic systems, where decay of a superposition of upper levels yields beats at the transition difference frequency; and the inverted "Type-II" or "Λ" systems, where decay to a superposition of lower levels does not yield beats [7,8].…”

High-resolution spectroscopy based on atomic coherences

“…The first observations of transient quantum beats were performed simultaneously by Dodd et al (1964) and Aleksandrov (1964). The improved apparatus used by Dodd et al (1967) in a more detailed study of the phenomenon is shown in figure 1. Zeeman quantum beats in cadmium vapour excited by the intercombination line 5 1S0-5 3P1 at 3261 As was chosen for this investigation.…”