  Topologically stable matters can have a long lifetime, even if
thermodynamically costly, when the thermal agitation is sufficiently low. A
magnetic skyrmion lattice (SkL) represents a unique form of long-range magnetic
order that is topologically stable, and therefore, a long-lived, metastable SkL
can form. Experimental observations of the SkL in bulk crystals, however, have
mostly been limited to a finite and narrow temperature region in which the SkL
is thermodynamically stable; thus, the benefits of the topological stability
remain unclear. Here, we report a metastable SkL created by quenching a
thermodynamically stable SkL. Hall-resistivity measurements of MnSi reveal
that, although the metastable SkL is short-lived at high temperatures, the
lifetime becomes prolonged (>> 1 week) at low temperatures. The manipulation of
a delicate balance between thermal agitation and the topological stability
enables a deterministic creation/annihilation of the metastable SkL by
exploiting electric heating and subsequent rapid cooling, thus establishing a
facile method to control the formation of a SkL.
