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arXiv · 1605.02449

New insights on frequency combinations and 'forbidden frequencies' in de Haas-van Alphen spectrum of \k{appa}-(ET) 2 Cu(SCN) 2

Alain Audouard·Jean-Yves Fortin·David Vignolles·Vladimir N. Laukhin·Nataliya D. Kushch·Eduard B. Yagubskii
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Abstract

De Haas-van Alphen oscillations of the organic metal \k{appa}-(ET) 2 Cu(SCN) 2 have been measured up to 55 T at liquid helium temperatures. The Fermi surface of this charge transfer salt is a textbook example of linear chain of orbits coupled by magnetic breakdown. Accordingly, the oscillation spectrum is composed of linear combinations of the frequencies linked to the $\alpha$ and magnetic breakdown-induced $\beta$ orbits. The field and temperature dependence of all the observed Fourier components, in particular the "forbidden frequency" $\beta$ -- $\alpha$ 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.

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Alain Audouard, Jean-Yves Fortin, David Vignolles, Vladimir N. Laukhin, Nataliya D. Kushch, Eduard B. Yagubskii. 2016-05-09. New insights on frequency combinations and 'forbidden frequencies' in de Haas-van Alphen spectrum of \k{appa}-(ET) 2 Cu(SCN) 2. https://doi.org/10.1088/0953-8984/28/27/275702

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