TY - JOUR

T1 - Generation of a squeezed state of an oscillator by stroboscopic back-action-evading measurement

AU - Vasilakis, G.

AU - Shen, H.

AU - Jensen, K.

AU - Balabas, M.

AU - Salart, D.

AU - Chen, B.

AU - Polzik, E. S.

PY - 2015

Y1 - 2015

N2 - Continuous observation of an oscillator results in quantum back-action, which limits the knowledge acquired by the measurement. A careful balance between the information obtained and the back-action disturbance leads to the standard quantum limit of precision. This limit can be surpassed by a measurement with strength modulated at twice the oscillator frequency, resulting in a squeezed state of the oscillator motion, as proposed decades ago1, 2, 3. Here, we report the generation of a squeezed state of an oscillator by a stroboscopic back-action-evading measurement. The oscillator is the spin of an atomic ensemble precessing in a magnetic field. The oscillator initially prepared nearly in the ground state is stroboscopically coupled to an optical mode of a cavity. A measurement of the output light results in a 2.2 ± 0.3 dB squeezed state of the oscillator. The demonstrated spin-squeezed state of 108 atoms with an angular spin variance of 8 × 10−10 rad2 is promising for magnetic field sensing. Generation of a

AB - Continuous observation of an oscillator results in quantum back-action, which limits the knowledge acquired by the measurement. A careful balance between the information obtained and the back-action disturbance leads to the standard quantum limit of precision. This limit can be surpassed by a measurement with strength modulated at twice the oscillator frequency, resulting in a squeezed state of the oscillator motion, as proposed decades ago1, 2, 3. Here, we report the generation of a squeezed state of an oscillator by a stroboscopic back-action-evading measurement. The oscillator is the spin of an atomic ensemble precessing in a magnetic field. The oscillator initially prepared nearly in the ground state is stroboscopically coupled to an optical mode of a cavity. A measurement of the output light results in a 2.2 ± 0.3 dB squeezed state of the oscillator. The demonstrated spin-squeezed state of 108 atoms with an angular spin variance of 8 × 10−10 rad2 is promising for magnetic field sensing. Generation of a

KW - back-action-evading measurement

KW - spin-squeezed state

U2 - 10.1038/nphys3280

DO - 10.1038/nphys3280

M3 - Article

VL - 11

JO - Nature Physics

JF - Nature Physics

SN - 1745-2473

ER -