  It is extraordinarely difficult to detect the extremely weak gravitomagnetic
(GM) field of even as large a body as the earth. To detect the GM field, the
gravitational analog of an ordinary magnetic field, in a modest terrestrial
laboratory should be that much more difficult. Here we show, however, that for
certain superconductor configuration and topologies, it should be possible to
detect a measurable GM field in the terrestrial laboratory, by using the
properties of superconductors imposed by quantum mechanical requirements. In
particular, we show that the GM Flux should be quantized in a superconductor
with non-vanishing genus, just like the ordinary magnetic flux. And this
magnetically induced, quantized GM Flux, for sufficiently high quantum number
and favorable geometries, should be distinguishable from the effects produced
by an ordinary magnetic field.
