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Acta Physica Sinica

Quantum tunnelling time of cold atom passing through a laser beam

Lin Tang, Jianhua Huang, Duan Zheng-Lu, Weiping Zhang, Zhou Zhao-Ying, Feng Yan-Ying, Zhu Rong, (1)华东师范大学物理系，光谱学与波谱学教育部重点实验室，上海 200062; (2)清华大学精密仪器系，北京 100084; (3)清华大学物理系，北京 100084

Published Jan 1, 2006• 1 citation
Publisher

Abstract

Atoms can be prepared at low temperatures by laser cooling. The center of mass motion of the cold atoms exhibits wave nature of quantum mechanics. In this paper, we study the quantum tunneling effect of a cold atomic beam propagating through a laser beam which is blue detuned. The blue detuned laser beam is physically equal to a quantum potential barrier. According to two-level model of atom, we systematically analyze the quantum reflection and transmission of the vector atomic matter wave with internal structures propagating through a laser beam. Quantum tunneling time the atomic beam spends in transmitting the laser beam is studied in details. Because of quantum wave nature, cold atoms tunneling through a laser beam can obviously have a completely different feature from that of a classical particle (hot atom).

DOI
10.7498/aps.55.6606

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