4 research outputs found
Detection of ultra-high resonance contrast in vapor cell atomic clocks
We propose and demonstrate a novel detection scheme of clock signals and
obtain an ultra-high resonance contrast above 90%. The precision of the
signal's detection and the signal-to-noise ratio (SNR) of atomic clock signal
is improved remarkably. The frequency stability in terms of Allan deviation has
been improved by an order for the new detection under the equivalent
conditions. We also investigate density effect which produces the splitting of
the transmission peak and consequently a narrower linewidth of Ramsey fringes.Comment: 5 pages, 4 figure
Measurement of Mass by Optical Forced Oscillation of Absorbing Particles Trapped in Air
We demonstrate the measurement of mass of the absorbing micro-particle
trapped in air by optical forced oscillation. When the trapping light intensity
is modulated sinusoidally, the particle in the trap undergoes forced
oscillation and the amplitude of the oscillation depends directly on the
modulated frequency. Based on a simple spring model, we fit the amplitudes
versus the modulated frequencies and obtain the stiffness of the optical trap
and the mass of the trapped particle. The fitting results show that, for a
certain particle, the stiffness varies linearly with the trapping light
intensity while the mass is consistent. The density of the micro-particle is
then estimated and could be used to classify different kinds of absorbing
particles, like C and CuO