We experimentally study optical homodyne and heterodyne detections with the same setup, which is flexible to manipulate the signal sideband modulation. When the modulation only generates a single signal sideband, the light field measurement by mixing the single sideband at ω0 ±? with a strong local oscillator at the carrier frequency ω0on a beam splitter becomes balanced heterodyne detection. When two signal sidebands at ω0 ±? 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.We experimentally study optical homodyne and heterodyne detections with the same setup, which is flexible to manipulate the signal sideband modulation. When the modulation only generates a single signal sideband, the light field measurement by mixing the single sideband at ω0 ±? with a strong local oscillator at the carrier frequency ω0on a beam splitter becomes balanced heterodyne detection. When two signal sidebands at ω0 ±? 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.

Science in China. Series G, Physics, mechanics & astronomy/Science in China. Series G, Physics, Mechanics & AstronomyJan 1, 20150 citations

Quantum theory of balanced homodyne detection

R. Loudon

Jan 1, 19861 citation

Coherent control of broadband vacuum squeezing

S. Chelkowski, H. Vahlbruch, K. Danzmann +1 more

We present the observation of optical fields carrying squeezed vacuum states at sideband frequencies from $10\phantom{\rule{0.3em}{0ex}}\mathrm{Hz}$ to above $35\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$ . The field was generated with type-I optical parametric oscillation below threshold at $1064\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ . A coherent, unbalanced classical modulation field at $40\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$ enabled the generation of error signals for stable phase control of the squeezed vacuum field with respect to a strong local oscillator. Broadband squeezing of approximately $\ensuremath{-}4\phantom{\rule{0.3em}{0ex}}\mathrm{dB}$ was measured with balanced homodyne detection. The spectrum of the squeezed field allows a quantum noise reduction of ground-based gravitational wave detectors over their full detection band, regardless of whether homodyne readout or radio-frequency heterodyne readout is used.We present the observation of optical fields carrying squeezed vacuum states at sideband frequencies from $10\phantom{\rule{0.3em}{0ex}}\mathrm{Hz}$ to above $35\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$. The field was generated with type-I optical parametric oscillation below threshold at $1064\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. A coherent, unbalanced classical modulation field at $40\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}$ enabled the generation of error signals for stable phase control of the squeezed vacuum field with respect to a strong local oscillator. Broadband squeezing of approximately $\ensuremath{-}4\phantom{\rule{0.3em}{0ex}}\mathrm{dB}$ was measured with balanced homodyne detection. The spectrum of the squeezed field allows a quantum noise reduction of ground-based gravitational wave detectors over their full detection band, regardless of whether homodyne readout or radio-frequency heterodyne readout is used.

arXiv:0704.3796Physical Review AApr 23, 200771 citations

Statistics of balanced homodyne detection

W. Vogel, Jens Grabow

Quantum Electronics and Laser Science ConferenceMay 10, 19920 citations

Recovering correlations in optomechanical heterodyne spectra for high-precision quantum displacement sensing

T. S. Monteiro, J. E. Lang

Homodyne and heterodyne detection represent "twin-pillars" of quantum displacement sensing using optical cavities, having permitted major breakthroughs including detection of gravitational waves and of the motion of quantum ground-state cooled mechanical oscillators. Both can suffer disadvantages as diagnostics in quantum optomechanics, either through symmetrisation (homodyne), or loss of correlations (heterodyne). We show that, for modest heterodyne beat frequencies ( $Ω\sim ω_M/10 \gg Γ$ ), judicious construction of the autocorrelation of the measured current can either recover (i) a spectrum with strong sidebands but without an imprecision noise floor (ii) a spectrum which is a hybrid, combining both homodyne and heterodyne sideband features. We simulate an experimental realisation with stochastic numerics and find excellent agreement with analytical quantum noise spectra. We term such retrospective recovery of lost heterodyne correlations "r-heterodyning": as the method simply involves post-processing of a normal heterodyne time signal, there is no additional experimental constraint other than on the magnitude of $Ω$ .Homodyne and heterodyne detection represent "twin-pillars" of quantum displacement sensing using optical cavities, having permitted major breakthroughs including detection of gravitational waves and of the motion of quantum ground-state cooled mechanical oscillators. Both can suffer disadvantages as diagnostics in quantum optomechanics, either through symmetrisation (homodyne), or loss of correlations (heterodyne). We show that, for modest heterodyne beat frequencies ($Ω\sim ω_M/10 \gg Γ$), judicious construction of the autocorrelation of the measured current can either recover (i) a spectrum with strong sidebands but without an imprecision noise floor (ii) a spectrum which is a hybrid, combining both homodyne and heterodyne sideband features. We simulate an experimental realisation with stochastic numerics and find excellent agreement with analytical quantum noise spectra. We term such retrospective recovery of lost heterodyne correlations "r-heterodyning": as the method simply involves post-processing of a normal heterodyne time signal, there is no additional experimental constraint other than on the magnitude of $Ω$.

arXiv:1703.05736Mar 16, 20170 citations

We present the observation of optical fields carrying squeezed vacuum states at sideband frequencies from

10\phantom{\rule{0.3em}{0ex}}\mathrm{Hz}

to above

35\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}

. The field was generated with type-I optical parametric oscillation below threshold at

1064\phantom{\rule{0.3em}{0ex}}\mathrm{nm}

. A coherent, unbalanced classical modulation field at

40\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}

enabled the generation of error signals for stable phase control of the squeezed vacuum field with respect to a strong local oscillator. Broadband squeezing of approximately $\ensuremath{-}4\phantom{\rule{0.3em}{0ex}}\mathrm{dB}$ was measured with balanced homodyne detection. The spectrum of the squeezed field allows a quantum noise reduction of ground-based gravitational wave detectors over their full detection band, regardless of whether homodyne readout or radio-frequency heterodyne readout is used.

Ω\sim ω_M/10 \gg Γ

), judicious construction of the autocorrelation of the measured current can either recover (i) a spectrum with strong sidebands but without an imprecision noise floor (ii) a spectrum which is a hybrid, combining both homodyne and heterodyne sideband features. We simulate an experimental realisation with stochastic numerics and find excellent agreement with analytical quantum noise spectra. We term such retrospective recovery of lost heterodyne correlations "r-heterodyning": as the method simply involves post-processing of a normal heterodyne time signal, there is no additional experimental constraint other than on the magnitude of

Ω