In this work, making use of time-resolved in situ joule heating of a two-dimensional electron gas (2DEG) in the Corbino geometry, we report bulk thermal conductance measurements for the $\nu =5/2$ and $\nu =7/3$ fractional quantum Hall (FQH) states for electron temperatures ranging from 20 to 150 mK. We compare our findings with a recent study by Melcer et al. [Nature (London) 625, 489 (2024)] that observed a finite bulk thermal conductivity ${\kappa }_{xx}$ in FQH states. In spite of the large size difference and the vastly different experimental schemes used to extract ${\kappa }_{xx}$, we find in large part that both experiments yield similar results and conclude that the bulk of FQH states thermally conducts and violate the Wiedemann-Franz law by a wide margin. Differences between both studies pertaining to particle-hole symmetry in the vicinity of the 5/2 FQH state are discussed in terms of the underlying many-body wave function forming the ground state whereby in one case an edge contribution was present and then subtracted, and in the other no edge transport was ever present due to the Corbino geometry used.

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• Fractional quantum Hall effect
• Thermal conductivity
• Thermodynamics
• Two-dimensional electron system