Honey-Like Heat Flow: A New Heat Transport Regime Discovered in Ultrathin Semiconductors

Why It Matters

By enabling intrinsic control of heat flow without redesigning material structures, this regime could boost performance, reliability, and energy efficiency of next‑generation electronic and photonic systems.

Key Takeaways

• Hydro‑thermoelastic transport merges phonon fluidity with stress‑induced heat redirection.
• Thermal diffusivity in MoS₂/MoSe₂ drops up to ten times lower.
• Heat can flow from cold to hot zones under specific strain conditions.
• Optothermal microscopy tracks heat at nanometre scale in real time.
• Intrinsic heat control could reshape thermal design of transistors and thermoelectrics.

Pulse Analysis

Heat dissipation remains a bottleneck for scaling modern microelectronics, especially as devices shrink to nanometre dimensions. Two‑dimensional semiconductors such as MoS₂ and MoSe₂ have attracted attention for their exceptional electronic properties, yet their thermal behavior has been difficult to predict. Conventional models assume heat spreads diffusively, but at the ultrathin limit, lattice vibrations (phonons) can interact collectively, creating fluid‑like dynamics that challenge those assumptions. Understanding these nuances is essential for engineers seeking to balance speed, power, and reliability in next‑gen chips.

The breakthrough reported in Nature Physics demonstrates that, in these 2D layers, heat transport enters a hydro‑thermoelastic regime where phonon hydrodynamics couples with stress‑induced lattice deformation. Using a cutting‑edge optothermal technique, researchers visualized heat propagation with nanometre precision, revealing a dramatic slowdown—thermal diffusivity reduced by an order of magnitude—and even instances of heat flowing from colder to hotter regions under specific strain. This dual‑phenomenon had never been observed together in semiconductors, highlighting a richer, more controllable thermal landscape than previously imagined.

From a commercial perspective, the ability to steer heat intrinsically could transform thermal management strategies across the semiconductor supply chain. Designers may embed strain‑engineered regions to trap or redirect heat, reducing reliance on bulky heat sinks and improving overall energy efficiency. Moreover, the same principles could enhance thermoelectric converters by maintaining temperature gradients longer, boosting power output. As the industry pushes toward heterogeneous integration and 3‑D stacking, mastering hydro‑thermoelastic transport may become a decisive advantage for firms aiming to deliver faster, cooler, and more sustainable devices.