Two-Frequency Multiphoton Heterodyne Detection

Since multiple-quantum optical direct detection has also been studied in great detail, it seems natural to investigate the behavior of such a detector in the presence of more than one frequency [7.16]. In this section, we obtain the response and the signal-to-noise power ratio (SNR) for a multiple-quantum absorption heterodyne receiver, with particular attention devoted to the simplest case, i.e., the mixing of two waves in a double-quantum infrared or optical device. 

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