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arXiv · 1110.3696

Quantum oscillations in the linear chain of coupled orbits: the organic metal with two cation layers theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2))

Alain Audouard·Jean-Yves Fortin·David Vignolles·Rustem B. Lyubovskii·Loïc Drigo·Fabienne Duc·Gena V. Shilov·Elena I. Zhilayeva·Rimma N. Lyubovskaya·Enric Canadell
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Abstract

Analytical formulae for de Haas-van Alphen (dHvA) oscillations in linear chain of coupled two-dimensional (2D) orbits (Pippard's model) are derived systematically taking into account the chemical potential oscillations in magnetic field. Although corrective terms are observed, basic (alpha) and magnetic breakdown-induced (beta and 2beta - alpha) orbits can be accounted for by the Lifshits-Kosevich (LK) and Falicov-Stachowiak semiclassical models in the explored field and temperature ranges. In contrast, the 'forbidden orbit' beta - alpha amplitude is described by a non-LK equation involving a product of two classical orbit amplitudes. Furthermore, strongly non-monotonic field and temperature dependence may be observed for the second harmonics of basic frequencies such as 2alpha and the magnetic breakdown orbit beta + alpha, depending on the value of the spin damping factors. These features are in agreement with the dHvA oscillation spectra of the strongly 2D organic metal theta- theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2)).

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Alain Audouard, Jean-Yves Fortin, David Vignolles, Rustem B. Lyubovskii, Loïc Drigo, Fabienne Duc, Gena V. Shilov, Elena I. Zhilayeva, Rimma N. Lyubovskaya, Enric Canadell. 2012-02-03. Quantum oscillations in the linear chain of coupled orbits: the organic metal with two cation layers theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2)). https://doi.org/10.1209/0295-5075%2F97%2F57003

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