The same overheating problem that happens to our laptops also plagues computer servers and data centers around the world. Understanding how heat moves through chips at the micro scale is essential for continuing to improve their performance. Now MIT researchers have demonstrated a new way to study how heat moves through multilayered materials, combining X-rays that penetrate multiple layers with laser pulses for delivering heat. The researchers used the technique to measure how heat moves inside a promising device for transistors and flexible electronics. The method was so precise it allowed the researchers to quantify the effect of a single micron-scale defect in the device, revealing a surprising fourfold reduction in the material’s ability to transfer heat at that spot. Blogger's Review: This new method can effectively study heat transfer in multilayered materials, which is crucial for developing higher power-density electronic devices. Researchers can use this method to design better chips, improving the performance and reliability of electronic devices.