Temperature measurement of cold atoms using single-atom transits and Monte Carlo simulation in a strongly coupled atom-cavity system

Abstract

We investigate the transmission of single-atom transits based on a strongly coupled cavity quantum electrodynamics system. By superposing the transit transmissions of a considerable number of atoms, we obtain the absorption spectra of the cavity induced by single atoms and obtain the temperature of the cold atom. The number of atoms passing through the microcavity for each release is also counted, and this number changes exponentially along with the atom temperature. Monte Carlo simulations agree closely with the experimental results, and the initial temperature of the cold atom is determined. Compared with the conventional time-of-flight (TOF) method, this approach avoids some uncertainties in the standard TOF and sheds new light on determining temperature of cold atoms by counting atoms individually in a confined space.

Cavity enhanced measurement of trap frequency in an optical dipole trap

“…However, this approach must induce some extra uncertainties, such as the spatial profile of the probe beam, and the intensity and the pointing fluctuations of the probe beam. [15] In addition, in some situations where a finite interspace exists, such as a cavity quantum electrodynamics (QED) system, imaging optics with a large numerical aperture to collect the fluorescence usually make the system complex.…”

“…Such a system enables not only a succession of experiments of quantum information processing [16][17][18] and a nonlinear process [19] with single atoms, but also atomic sensing. [15,[20][21][22][23] In a cavity QED system, the vacuum Rabi splitting is approximately proportional to the square root of the effective average number ( √ N) of atoms interacting with the cavity. [24,25] The number of coupling atoms alters the transmission of a weak resonant probe beam from the cavity.…”

Experimental investigation of the statistical distribution of single atoms in cavity quantum electrodynamics

“…This was based on the measurement of the second-order correlation function g 2 (τ) of an atom laser and pseudo-thermal atomic beams in an HBT type experiment, where τ is the time delay [6]. Sensitive probing and manipulation of single atoms with the quantized electromagnetic field in the cavity mode is possible in the strong coupling regime of a cavity quantum electrodynamics (QED) system, where the decoherence is much smaller than the coupling [10][11][12][13]. In this letter we describe an experiment in which we also counted single atoms using a high finesse optical microcavity, but the atomic beam is directly derived from a magneto-optical trap (MOT).…”