000225833 001__ 225833
000225833 005__ 20181203024548.0
000225833 0247_ $$2doi$$a10.1103/PhysRevX.7.011001
000225833 022__ $$a2160-3308
000225833 02470 $$2ISI$$a000391318500001
000225833 037__ $$aARTICLE
000225833 245__ $$aAppearance and Disappearance of Quantum Correlations in Measurement-Based Feedback Control of a Mechanical Oscillator
000225833 260__ $$bAmerican Physical Society$$c2017$$aCollege Pk
000225833 269__ $$a2017
000225833 300__ $$a14
000225833 336__ $$aJournal Articles
000225833 520__ $$aQuantum correlations between imprecision and backaction are a hallmark of continuous linear measurements. Here, we study how measurement-based feedback can be used to improve the visibility of quantum correlations due to the interaction of a laser field with a nanomechanical oscillator. Backaction imparted by the meter laser, due to radiation-pressure quantum fluctuations, gives rise to correlations between its phase and amplitude quadratures. These quantum correlations are observed in the experiment both as squeezing of the meter field fluctuations below the vacuum level in a homodyne measurement and as sideband asymmetry in a heterodyne measurement, demonstrating the common origin of both phenomena. We show that quantum feedback, i.e., feedback that suppresses measurement backaction, can be used to increase the visibility of the sideband asymmetry ratio. In contrast, by operating the feedback loop in the regime of noise squashing, where the in-loop photocurrent variance is reduced below the vacuum level, the visibility of the sideband asymmetry is reduced. This is due to backaction arising from vacuum noise in the homodyne detector. These experiments demonstrate the possibility, as well as the fundamental limits, of measurement-based feedback as a tool to manipulate quantum correlations.
000225833 700__ $$0245939$$g201058$$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$aSudhir, V.
000225833 700__ $$0246503$$g225172$$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$aWilson, D. J.
000225833 700__ $$0246969$$g222928$$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$aSchilling, R.
000225833 700__ $$0246956$$g230194$$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$aSchuetz, H.
000225833 700__ $$0249431$$g260066$$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$aFedorov, S. A.
000225833 700__ $$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$0246878$$g222921$$aGhadimi, A. H.
000225833 700__ $$aNunnenkamp, A.
000225833 700__ $$0244694$$g182444$$uEcole Polytech Fed Lausanne, Inst Condensed Matter Phys, CH-1015 Lausanne, Switzerland$$aKippenberg, T. J.
000225833 773__ $$j7$$tPhysical Review X$$k1$$q011001
000225833 909C0 $$0252348$$pLPQM
000225833 909CO $$particle$$ooai:infoscience.tind.io:225833$$pSB$$pSTI
000225833 917Z8 $$x222695
000225833 937__ $$aEPFL-ARTICLE-225833
000225833 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000225833 980__ $$aARTICLE