We describe the details of crystal growth of Sr2RuO4 by a floating-zone met
hod. The superconducting transition temperature T-c can be controlled by ad
justment of crystal growth conditions. By optimizing the growth conditions,
crystals with T-c up to 1.50 K have been obtained. In addition, we observe
d three kinds of two-phase composite structures grown under different condi
tions. They include (I) a Sr2RuO4-Ru eutectic system, in which lamellae of
Ru are embedded in the primary phase of Sr2RuO4, resulting in a remarkable
enhancement in T-c by a factor of about 2; (2) epitaxial-like intergrowth o
f ferromagnetic SrRuO3, on Sr2RuO4; and (3) eutectic growth of Sr2RuO4 and
a new insulating phase with the possible composition of Sr3RuO5+delta. (C)
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