Models of reduced-noise, probabilistic linear amplifiers

الأصل · EN

We construct an amplifier that interpolates between a nondeterministic, immaculate linear amplifier and a deterministic, ideal linear amplifier and beyond to nonideal linear amplifiers. The construction involves cascading an immaculate linear amplifier that has amplitude gain g₁ with a (possibly) nonideal linear amplifier that has gain g₂. With respect to normally ordered moments, the device has output noise μ²(G²-1) where G=g₁ g₂ is the overall amplitude gain and μ² is a noise parameter. When μ²≥1, our devices realize ideal (μ²=1) and nonideal (μ²>1) linear amplifiers. When 0≤μ²<1, these devices work effectively only over a restricted region of phase space and with some subunity success probability p. We investigate the performance of our μ²-amplifiers in terms of a gain-corrected probability-fidelity product and the ratio of input to output signal-to-noise ratios corrected for success probability.