Session KP01 - Poster Session III.
POSTER session, Tuesday afternoon, March 23
Exhibit Hall, GWCC
In an effort to help students develop a clear picture of the physics of driven atoms, we have constructed a mechanical model. Using a mechanical mass-spring oscillator, a sonic ranger, and a voltage controlled stepper motor, we are investigating the oscillator's response to chopped forcing functions. The stepper motor coupling to the mass is designed so that the phase of the motor can be controlled from pulse to pulse. This allows for each pulse to be sent with the same phase, with a predetermined different phase or with a random phase. This system is analogous to the classical Lorentz model of the atom driven by a chopped optical field. This extreme amplitude modulation gives rise to a variety of interesting phenomena, including optical Ramsey fringes (large dipole atom response for detuning * cycle time = 2 pi). These results will be compared to numerical solutions of an isolated Lorentz model atom interacting with a similar train of short laser pulses.