Pair creation of neutral particles in a vacuum by external electromagnetic fields in 2+1 di.pdf

a r X i v : h e p - t h / 9 9 0 9 0 4 5 v 1 8 S e p 1 9 9 9 Pair creation of neutral particles in a vacuum by external electromagnetic fields in 2+1 dimensions ? Qiong-gui Lin? China Center of Advanced Science and Technology (World Laboratory), P.O.Box 8730, Beijing 100080, People’s Republic of China and Department of Physics, Zhongshan University, Guangzhou 510275, People’s Republic of China ? Neutral fermions of spin 1 2 with magnetic moment can interact with electromagnetic fields through nonminimal coupling. In 2+1 dimensions the electromagnetic field strength plays the same role to the magnetic mo- ment as the vector potential to the electric charge. This duality enables one to obtain physical results for neutral particles from known ones for charged particles. We give the probability of neutral particle-antiparticle pair creation in the vacuum by non-uniform electromagnetic fields pro- duced by constant uniform charge and current densities. PACS number(s): 03.70.+k, 11.10.Kk, 11.15.Tk ?published in J. Phys. G 25 (1999) 1793-1795. c?IOP publishing Ltd. 1999 ?E-mail addresses: qg lin@163.net, stdp@zsu.edu.cn ?Mailing address 1 Pair creation of charged particles in the vacuum by an external electric field was first studied by Schwinger several decades ago [1]. Related problems have been discussed by many authors, for example, in Refs. [2-6]. Pure magnetic fields do not lead to pair creation. However, inclusion of a magnetic field changes the result for a pure electric field. This has been studied by several authors [7-11]. The probability of pair creation in the vacuum was also calculated in lower dimensions [11] and in more general dimensions [8]. Similar subjects are now widely discussed in string and black hole theory. In this paper we extend the subject to neutral particles of spin 1 2 . Neutral particles with magnetic moment can interact with electromagnetic fields through nonminimal coupling. The Aharonov-Casher effect [12] is a well known indication f