The Japanese Journal of Applied Physics (JJAP) is an international journal for the advancement and dissemination of knowledge in all fields of applied physics. JJAP is a sister journal of the Applied Physics Express (APEX) and is published by IOP Publishing Ltd on behalf of the Japan Society of Applied Physics (JSAP).

JJAP publishes articles that significantly contribute to the advancements in the applications of physical principles as well as in the understanding of physics in view of particular applications in mind. Subjects covered by JJAP include the following fields:

Semiconductors, dielectrics, and organic materials
Photonics, quantum electronics, optics, and spectroscopy
Spintronics, superconductivity, and strongly correlated materials
Device physics including quantum information processing
Physics-based circuits and systems
Nanoscale science and technology
Crystal growth, surfaces, interfaces, thin films, and bulk materials
Plasmas, applied atomic and molecular physics, and applied nuclear physics
Device processing, fabrication and measurement technologies, and instrumentation
Cross-disciplinary areas such as bioelectronics/photonics, biosensing, environmental/energy technologies, and MEMS