Yes, there are several publications that focus on the electromagnetic theory and applications section of the UPSC Physics optional. These publications provide comprehensive coverage of the topics related to electromagnetic theory, including both theoretical concepts and their practical applications. Here are some of the popular publications for this section:

1. Introduction to Electrodynamics by David J. Griffiths:
This book is widely regarded as one of the best introductory textbooks on electrodynamics. It covers all the fundamental concepts of electromagnetic theory, including Maxwell's equations, electrostatics, magnetostatics, electromagnetic waves, and more. The book provides a clear and concise explanation of the concepts, supported by numerous examples and exercises.

2. Classical Electrodynamics by John David Jackson:
Considered a classic in the field, this book offers a comprehensive treatment of classical electrodynamics. It covers topics such as electrostatics, magnetostatics, electromagnetic waves, radiation, and relativistic electrodynamics. The book provides a rigorous mathematical approach to the subject, making it suitable for advanced students.

3. Electromagnetic Field Theory Fundamentals by Bhag Singh Guru and Hüseyin R. Hiziroglu:
This book focuses on the fundamentals of electromagnetic field theory and provides a thorough understanding of the subject. It covers topics such as vector analysis, electrostatics, magnetostatics, electromagnetic waves, transmission lines, and more. The book also includes numerous solved examples and practice problems to reinforce the concepts.

4. Electromagnetic Theory and Electrodynamics by Satya Prakash:
This book is specifically designed for the UPSC examination and covers the electromagnetic theory section in detail. It covers topics such as electrostatics, magnetostatics, electromagnetic waves, transmission lines, and more. The book includes multiple-choice questions, objective type questions, and previous years' UPSC question papers to help students practice and assess their understanding.

These publications provide a solid foundation in electromagnetic theory and its applications. They are highly recommended for UPSC Physics optional aspirants as they cover the syllabus comprehensively and provide ample practice material. By studying these publications, candidates can gain a deep understanding of electromagnetic theory and effectively apply it to solve problems in various real-world scenarios.