The Micromaser

The Micromaser is a defining experiment of cavity QED. The superconducting cavities of the micromaser have one of the highest Q factors of any cavity made today. Using these cavities We reach well into the strong coupling regime where the quantum mechanical propoerties of the atom are significantly modified. The interior of the micromaser cavity is actually a good example of the impervious box used in the Schroedingers cat analogy.

Quantum Information

We are using the micromaser to perform quantum information experiments by investigating methods of writing information onto the phase of a field mode. This is iteresting for two reasons, firstly we have a great deal of control over the phase, and we can, in principle move from a simultaneous superpositon of all phases (the fock state) to a well defined phase state by changing the operating conditions (interaction time and cavity frequency) of the micromaser. Phase is a continuously variable quantity, thus it is possible to perform computations using information written onto a medium that is well isolated from the environment and where all parameters of the interaction are controled.

We are also using the micromaser as a demonstration of a one dimensional cluster state to propagate information down a line of entangled atoms.

Laser Physics

The origin of linewidth in a laser is attributed to Heisenburg's Uncertainty Principle in the following way; The lasing medium itself is comprised of atoms whose response to the light is proportional to the energy it contains (E) thereby contributing to a phase uncertainty (T) via the famour relationship $\delta E\delta T>h$ and therefore leading to a mimimum linewidth that is determined by the number of atoms in the lasing medium. Observing this effect is effectively impossible in a normal laser, but in the micromaser we can observe each atom as it contributes to the field in the cavity. In effect we will be able to watch Heisenburg's uncertainty principle in operation.

Precision Tests of Relativity

We probe Special Relativity using precision measurements of subtle differences between Doppler shift and Time Dilation in a moving atom. This experiment is in the early days of its data analysis phase. More information will be presented as it becomes available.

"We never experiment with just one atom, in thought experiments we sometimes assume that we do, this invariably entails ridiculous consequences." Erwin Schrödinger