Selected Publications

## Squeezing of Quantum Noise of Motion in a Micromechanical Resonator

J.-M. Pirkkalainen, E. Damskägg, M. Brandt, F. Massel, M.A. Sillanpää

A pair of conjugate observables, such as the quadrature amplitudes of harmonic motion, have fundamental fluctuations that are bound by the Heisenberg uncertainty relation. However, in a squeezed quantum state, fluctuations of a quantity can be reduced below the standard quantum limit, at the cost of increased fluctuations of the conjugate variable. Here we prepare a nearly macroscopic moving body, realized as a micromechanical resonator, in a squeezed quantum state. We obtain squeezing of one quadrature amplitude 1.1±0.4dB below the standard quantum limit, thus achieving a long-standing goal of obtaining motional squeezing in a macroscopic object.

Phys. Rev. Lett 115, 24 (2015)

doi: 10.1103/PhysRevLett.115.243601