论文标题
反应性，耗散和限制的非线性对超导谐振参数放大器行为的影响
Effects of reactive, dissipative and rate-limited nonlinearity on the behaviour of superconducting resonator parametric amplifiers
论文作者
论文摘要
我们提出了一种形式主义，用于通过具有混合反应性/耗散特征的速率限制非线性的谐振器建模参数放大，并且与超导设备特别相关。假定非线性的特征是单个状态参数，该参数响应了以有限的响应时间存储在谐振器中的能量的变化。我们展示了如何根据一组三个无量纲参数计算，表征和优化的泵谐振器的工作点和小信号放大行为。然后，用简单的一阶模型非线性来说明形式主义，并在讨论的超导体中通过准粒子产生扩增对扩增的含义。在整个过程中，我们描述了如何通过稳态测量实验确定表征设备所需的参数。本文的关键结果是，非线性机制的限制并不排除放大，尽管它确实限制了可以实现的带宽。
We present a formalism for modelling parametric amplification by resonators subject to rate-limited nonlinearity of mixed reactive/dissipative character, with particular relevance to superconducting devices. The non-linearity is assumed to be characterised by a single state parameter, which responds to changes in the energy stored in the resonator with finite response time. We show how the operating point and small signal amplification behaviour of the pumped resonator can be calculated, characterised and optimised in terms of a set of three dimensionless parameters. The formalism is then illustrated with a simple, first-order, model nonlinearity and the implications for amplification via quasiparticle generation in a superconductor discussed. Throughout we describe how the parameters needed to characterise the device can be determined experimentally from steady-state measurements. A key result of this paper is that rate-limiting of a nonlinear mechanism does not preclude amplification, although it does limit the bandwidth over which it may be achieved.
