Quantum Nondemolition Measurement of Photon-Number Distribution for a Two-Mode Field**The project supported by Science Research Foundation of Education Committee of Fujian Province and Funds from Fuzhou University

Abstract

We propose a quantum nondemolition measurement of the photon-number distribution for a two-mode cavity field. In the scheme two sequences of two-level atoms interact dispersively with the respective cavity modes and resonantly with two classical fields, and then are detected continually. The field finally reduces to a two-mode Fock state. The probability of collapsing to a given Fock state is determined by the initial photon-number distribution. The scheme can be easily generalized to a field with N modes.