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arXiv · 2001.11416

Extreme Fermi surface smearing in a maximally disordered concentrated solid solution

Hannah C. Robarts·Thomas E. Millichamp·Daniel A. Lagos·Jude Laverock·David Billington·Jonathan A. Duffy·Daniel O'Neill·Sean R. Giblin·Jonathan W. Taylor·Grazyna Kontrym-Sznajd·Malgorzata Samsel-Czekala·Hongbin Bei·Sai Mu·German D. Samolyuk·G. Malcolm Stocks·Stephen B. Dugdale
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Abstract

We show that the Fermi surface can survive the presence of extreme compositional disorder in the equiatomic alloy Ni$_{0.25}$Fe$_{0.25}$Co$_{0.25}$Cr$_{0.25}$. Our high-resolution Compton scattering experiments reveal a Fermi surface which is smeared across a significant fraction of the Brillouin zone (up to 40\% of $\frac{2\pi}{a}$). The extent of this smearing and its variation on and between different sheets of the Fermi surface has been determined, and estimates of the electron mean-free-path and residual resistivity have been made by connecting this smearing with the coherence length of the quasiparticle states.

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Hannah C. Robarts, Thomas E. Millichamp, Daniel A. Lagos, Jude Laverock, David Billington, Jonathan A. Duffy, Daniel O'Neill, Sean R. Giblin, Jonathan W. Taylor, Grazyna Kontrym-Sznajd, Malgorzata Samsel-Czekala, Hongbin Bei, Sai Mu, German D. Samolyuk, G. Malcolm Stocks, Stephen B. Dugdale. 2020-01-30. Extreme Fermi surface smearing in a maximally disordered concentrated solid solution. https://doi.org/10.1103/physrevlett.124.046402

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