Homodyne coherent quantum noise cancellation in a hybrid optomechanical force sensor

Abstract

In this paper, we propose an experimentally viable scheme to enhance the sensitivity of force detection in a hybrid optomechanical setup assisted with squeezed vacuum injection, beyond the standard quantum limit (SQL). The scheme is based on a combination of the coherent quantum noise cancellation (CQNC) strategy with a variational homodyne detection of the cavity output spectrum in which the phase of the local oscillator is optimized. In CQNC, realizing a negative-mass oscillator in the system leads to exact cancellation of the backaction noise from the mechanics due to destructive quantum interference. Squeezed vacuum injection enhances this cancellation and allows sub-SQL sensitivity to be reached in a wide frequency band and at much lower input laser powers. We show here that the adoption of variational homodyne readout enables us to enhance this noise cancellation up to 40 dB compared to the standard case of detection of the optical output phase quadrature, leading to a remarkable force sensitivity of the order of 10 −19 N/ √Hz, 2-order enhancement compared to the standard case. Moreover, we show that at nonzero cavity detuning, the signal response can be amplified at a level 3-to 5-times larger than that in the standard case without variational homodyne readout, improving the signal-to-noise-ratio (SNR).

Dynamics of Rényi-2 correlations in optomechanics

“…Remarkably, the hierarchical inequality (1/2)I R E R G holds no matter what C is. Figures 2-4 suggests that large quantum correlations could be achieved between the two mechanical modes at low temperatures by using a large two-mode squeezing parameter r, and a large optomechanical cooperativity C. Noteworthy, the optimization of the system parameters is a non trivial task, however, one could follow the approach in [67][68][69]. For more investigation of the effects of the parameters n th , r and C, we plot in figure 5 the steady-state Rényi-2 correlations of the two mechanical modes as functions of the thermal phonons number n th for r = 1 and C = 2500 (n cav = 10 5 ) (panel (a)), the squeezing parameter r for n th = 100 (T = 50 mK) and C = 1000 (n cav = 4 × 10 4 ) (panel (b)) and the optomechanical cooperativity C for n th = 100 (T = 50 mK) and r = 1 (panel (c)).…”

Light as quantum back-action nullifying meter

“…The CQNC [49,50] uses an auxiliary system which is coupled to the main system. The auxiliary system is to be synthesized [51][52][53] such that the QBA noise from the main system cancel with the noise from the auxiliary system. The success of CQNC depends on the finetuning of the auxiliary system.…”

Negative cavity photon spectral function in an optomechanical system with two parametrically-driven mechanical oscillators

“…OMSs have been applied in a variety range of applications including ultraprecision quantum sensing and measurement [4][5][6][7][8][9][10][11][12][13][14][15][16] , quantum illumination or quantum radar 17,18 , cooling of the MO [19][20][21] , generation of entanglement [22][23][24][25][26][27] , synchronization of MOs [28][29][30][31] , generation of quadrature squeezing and amplification [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46] , realizing the dynamical Casimir effect-based nonclassical radiation sources [47][48][49][50][51][52] , optomechanically ...…”