Almog R, Zaitsev S, Shtempluck O, Buks E
Department of Electrical Engineering, Technion, Haifa 32000, Israel.
Phys Rev Lett. 2007 Feb 16;98(7):078103. doi: 10.1103/PhysRevLett.98.078103.
We study mechanical amplification and noise squeezing in a nonlinear nanomechanical resonator driven by an intense pump near its dynamical bifurcation point, namely, the onset of Duffing bistability. Phase sensitive amplification is achieved by a homodyne detection scheme, where the displacement detector's output, which has a correlated spectrum around the pump frequency, is down-converted by mixing with a local oscillator operating at the pump frequency with an adjustable phase. The down-converted signal at the mixer's output could be either amplified or deamplified, yielding noise squeezing, depending on the local oscillator phase.
我们研究了在一个非线性纳米机械谐振器中的机械放大和噪声压缩，该谐振器由一个靠近其动态分岔点（即达芬双稳性的起始点）的强泵浦驱动。通过零差检测方案实现相位敏感放大，其中位移探测器的输出（在泵浦频率附近具有相关频谱）通过与一个以泵浦频率运行且相位可调的本地振荡器混频进行下变频。混频器输出处的下变频信号根据本地振荡器相位的不同，可能被放大或被衰减，从而产生噪声压缩。
