•In real samples –random pinning = locally broken symmetry
Ø
Ø No long range order for Db4
ØNo first order
transition!!!
•If pinning is weak “quasi-long-range
order” remains
ØBragg glass -
qno topological defects
qPower law Bragg peaks
•Naterman-92
•Giamarchi & Ledousal 95