%0 Journal Article %T Experimental study of balanced optical homodyne and heterodyne detection by controlling sideband modulation %A Wei Li %A Zengming Meng %A Xudong Yu %A Jing Zhang %J Physics %D 2015 %I arXiv %R 10.1007/s11433-015-5718-z %X We experimentally study optical homodyne and heterodyne detections with a same setup, which is flexible to manipulate the signal sideband modulation. When the modulation only generate a single signal sideband, the light field measurement by mixing the single sideband at $\omega_{0}+\Omega$ with a strong local oscillator at the carrier frequency $\omega_{0}$ on a beam splitter become balanced heterodyne detection. When two signal sidebands at $\omega_{0}\pm\Omega$ are generated and the relative phase of the two sidebands is locked, this measurement corresponds to optical balanced homodyne detection. With this setup, we may confirm directly that the signal-to-noise ratio with heterodyne detection is two-fold worse than that with homodyne detection. This work will have important applications in quantum state measurement and quantum information. %U http://arxiv.org/abs/1508.04974v1