  An interesting proposal for detecting gravitational waves involves quantum
metrology of Bose-Einstein condensates (BECs). We consider a forced modulation
of the BEC trap, whose frequency matches that of an incoming continuous
gravitational wave. The trap modulation induces parametric resonance in the
BEC, which in turn enhances sensitivity of the BEC to gravitational waves. We
find that such a BEC detector could potentially be used to detect gravitational
waves across several orders of magnitude in frequency, with the sensitivity
depending on the speed of sound, size of the condensate, and frequency of the
phonons. We outline a possible BEC experiment and discuss the current
technological limitations. We also comment on the potential noise sources as
well as what is necessary for such a detector to become feasible.
