tailieunhanh - Advances in optical and photonic devices Part 18

Tham khảo tài liệu 'advances in optical and photonic devices part 18', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 17 Ultra-Sensitive Optical Atomic Magnetometers and Their Applications Igor Savukov Los Alamos National Laboratory USA 1. Introduction In this chapter we overview the most sensitive contemporary atomic magnetometers AM that are based on high-density alkali-metal vapors. These magnetometers are considered in a broader content of other magnetometers and their applications. The principles of the operation of the AMs are explained for better understanding of this topic. One point of focus in this chapter which establishes the connection to the title of this book is about the relation between lasers and most sensitive atomic magnetometers. The chapter is organized in the following way. After general introduction to the AMs and the applications of magnetometers the principles of the operation of optical atomic magnetometers are given. With this background information next so-called SERF magnetometers and their features are discussed. Then the discussion continues to the topic about the operation of SERF magnetometers in the non-SERF regime. Finally after covering the principles and theory we return to some most notable applications of atomic magnetometers. Since their discovery lasers have revolutionized many fields - the field of AMs or magnetometers in general is no exception. Before the advent of lasers AMs were based on discharge lamps which though relatively simple and inexpensive light sources did not provide enough power and had some other drawbacks for the realization of maximum sensitivity that can be achieved with atomic magnetometers. In a comparison of sensitivity of the state-of-the-art Cs magnetometers based on a Cs discharge lamp and a semiconductor laser made in Ref. Groeger et al. 2005 the lamp Cs magnetometer had sensitivity of 25 fT Hz1 2 that was lower than that of the same but laser-based magnetometer 15 fT Hz1 2. For most sensitive magnetometers the difference is expected much more significant although there is no investigation of this question in .