The research team led by Gao Peng at the Center for Quantum Materials Science and Electron Microscope Laboratory, School of Physics, Peking University, has triumphantly accomplished sub-nanometer-level measurements of temperature fields and interfacial thermal resistance, employing fast electron inelastic scattering spectroscopy within electron microscopes. Furthermore, they have unveiled the microscopic mechanisms governing the thermal transport of interfacial phonons across different interfaces.