Thermodynamics of $T_{\rm c}$ suppression in far-overdoped Tl$_2$Ba$_2$CuO$_6$

Ayanesh Maiti; David M. Broun; Seunghyun Khim; Michal Moravec; Antony Carrington; Carsten Putzke; Vivek Mishra; Peter Hirschfeld; Andrew P. Mackenzie; Andreas W. Rost

arXiv · 2609.01213

Thermodynamics of $T_{\rm c}$ suppression in far-overdoped Tl$_2$Ba$_2$CuO$_6$

Ayanesh Maiti·David M. Broun·Seunghyun Khim·Michal Moravec·Antony Carrington·Carsten Putzke·Vivek Mishra·Peter Hirschfeld·Andrew P. Mackenzie·Andreas W. Rost

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Abstract

The physical origin of the suppression of superconductivity with hole doping in overdoped cuprates remains unclear. We measure the electronic specific heat of microgram-scale Tl$_2$Ba$_2$CuO$_6$ crystals and find sharp superconducting anomalies persisting far into the overdoped regime. A weak-coupling BCS-like framework incorporating the known Fermi surface and cation disorder quantitatively reproduces the observed anomalies for $T_{\rm c}=14$-$25$ K and their weak doping dependence. The results show $T_{\rm c}(p)$ to be driven predominantly by a smoothly decreasing pairing strength.

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Ayanesh Maiti, David M. Broun, Seunghyun Khim, Michal Moravec, Antony Carrington, Carsten Putzke, Vivek Mishra, Peter Hirschfeld, Andrew P. Mackenzie, Andreas W. Rost. 2026-09-01. Thermodynamics of $T_{\rm c}$ suppression in far-overdoped Tl$_2$Ba$_2$CuO$_6$. https://arxiv.org/abs/2609.01213

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