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arXiv · 2203.16526

Tracking the evolution from isolated dimers to many-body entanglement in NaLu$_x$Yb$_{1-x}$Se$_2$

Luke Pritchard Cairns·Ryan Day·Shannon Haley·Nikola Maksimovic·Josue Rodriguez·Hossein Taghinejad·John Singleton·James G. Analytis
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Abstract

We synthesize homogeneous compositions of NaLu$_x$Yb$_{1-x}$Se$_2$, connecting non-magnetic NaLuSe$_2$ to the triangular lattice spin liquid candidate NaYbSe$_2$. Thermal and magnetic properties are studied as the system evolves from one with dilute magnetic defects to one of a dense magnetic lattice. The field and temperature dependent heat capacity show the carriers of entropy crossover from isolated magnetic ions to a correlated lattice borne from spin dimers. For the dilute system we estimate the single ion anisotropy $(g_\perp/g_\parallel =3.13)$ and also the dimer exchange couplings $J_\parallel(=5.4$~K) and $J_\perp(=9.6$~K), in order to draw comparison to the half-doped and full magnetic compounds.

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Luke Pritchard Cairns, Ryan Day, Shannon Haley, Nikola Maksimovic, Josue Rodriguez, Hossein Taghinejad, John Singleton, James G. Analytis. 2022-03-30. Tracking the evolution from isolated dimers to many-body entanglement in NaLu$_x$Yb$_{1-x}$Se$_2$. https://doi.org/10.1103/physrevb.106.024404

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