Effect of unconventional current-phase relation of Josephson junction on escape rate in ac SQUID

The escape rate of S -> R switching (from superconducting S state to unstable resistive R state) in an ac SQUID on Josephson junction with unconventional current-phase relation was investigated. We used two types of currentphase relations with additional terms to the first harmonic sin phi: a case of the second harmonic sin2 phi and a case of the fractional term sin(phi/2). It was shown that escape rate can exhibit qualitative features in the case of junctions with unconventional current-phase relations.