Renormalization Group Limit Cycle for Three-Stranded DNA
  We show that there exists an Efimov-like three strand DNA bound state at the duplex melting point and it is described by a renormalization group limit cycle. A nonperturbative RG is used to obtain this result in a model involving short range pairing only. Our results suggest that Efimov physics can be tested in polymeric systems. 
Tanmoy Pal, Poulomi Sadhukhan and Somendra M. Bhattacharjee
cond-mat.soft cond-mat.stat-mech quant-ph