We study minimal surfaces
in the unit sphere S3 that are one-parameter families of circles. Minimal
surfaces in ℝ3 foliated by circles were first investigated by Riemann, and a
hundred years later Lawson constructed examples of such surfaces in S3. We
prove that in S3 only two types of minimal surfaces are foliated by circles
crossing the principal lines at a constant angle. The first type of surfaces
are foliated by great circles that are bisectrices of the principal lines, and
we show that these are the examples of Lawson. The second type, which
are new in the literature, are families of small circles, and the circles are
principal lines. We give a constructive formula for these surfaces and an
application to the theory of minimal foliated semisymmetric hypersurfaces in
ℝ4.
Keywords
minimal surfaces in S3,
Clifford torus, Lawson torus, harmonic map, foliated
semisymmetric hypersurface, minimal hypersurface, nonlinear
elliptic system