title: New insights on frequency combinations and 'forbidden frequencies' in the de Haas-van Alphen spectrum of κ-(ET)2Cu(SCN)2.
abstract: de Haas-van Alphen oscillations of the organic metal κ-(ET)2Cu(SCN)2have been measured up to 55 T at liquid helium temperatures. The Fermi surface of this charge transfer salt is a textbook example of a linear chain of orbits coupled by magnetic breakdown. Accordingly, the oscillation spectrum is composed of linear combinations of the frequencies linked to the α and magnetic breakdown-induced β orbits. The field and temperature dependence of all the observed Fourier components, in particular the 'forbidden frequency' [Formula: see text] which cannot correspond to a classical orbit, are quantitatively accounted for by analytical calculations based on a second order development of the free energy, i.e. beyond the first order Lifshitz-Kosevich formula.
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses (UPR 3228 CNRS, INSA, UGA, UPS) 143 avenue de Rangueil, F-31400 Toulouse, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Audouard
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Fortin
authors.forename: David
authors.initials: D
authors.lastname: Vignolles
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Laukhin
authors.forename: Nataliya D
authors.initials: ND
authors.lastname: Kushch
authors.forename: Eduard B
authors.initials: EB
authors.lastname: Yagubskii