Characterization of a multimode coplanar waveguide parametric amplifier

TL;DR

This paper presents a detailed characterization of a flux-tunable Josephson parametric amplifier using higher resonator modes, demonstrating quantum-limited noise performance and low added noise in both degenerate and nondegenerate modes.

Contribution

It introduces a novel multimode Josephson parametric amplifier with on-chip flux tuning and compares its degenerate and nondegenerate amplification performance.

Findings

Achieves quantum-limited noise performance in both modes

Added noise can be less than 0.5 photons at low gain

Utilizes higher modes of a flux-tunable resonator for amplification

Abstract

We characterize a novel Josephson parametric amplifier based on a flux-tunable quarter-wavelength resonator. The fundamental resonance frequency is ~1GHz, but we use higher modes of the resonator for our measurements. An on-chip tuning line allows for magnetic flux pumping of the amplifier. We investigate and compare degenerate parametric amplification, involving a single mode, and nondegenerate parametric amplification, using a pair of modes. We show that we reach quantum-limited noise performance in both cases, and we show that the added noise can be less than 0.5 added photons in the case of low gain.