Noiseless nonreciprocity in a parametric active device

TL;DR

This paper proposes a noiseless, magnetic-field-free, on-chip nonreciprocal device using parametric modulation, suitable for quantum applications, avoiding dissipation and magnetic materials.

Contribution

It introduces a novel, reversible, parametric device that achieves nonreciprocity without magnetic components or dissipation, enabling integration with superconducting circuits.

Findings

Operates noiselessly due to reversible design

Eliminates need for magnetic materials in nonreciprocal devices

Suitable for on-chip quantum information processing

Abstract

Nonreciprocal devices such as circulators and isolators belong to an important class of microwave components employed in applications like the measurement of mesoscopic circuits at cryogenic temperatures. The measurement protocols usually involve an amplification chain which relies on circulators to separate input and output channels and to suppress backaction from different stages on the sample under test. In these devices the usual reciprocal symmetry of circuits is broken by the phenomenon of Faraday rotation based on magnetic materials and fields. However, magnets are averse to on-chip integration, and magnetic fields are deleterious to delicate superconducting devices. Here we present a new proposal combining two stages of parametric modulation emulating the action of a circulator. It is devoid of magnetic components and suitable for on-chip integration. As the design is free of any dissipative elements and based on reversible operation, the device operates noiselessly, giving it an important advantage over other nonreciprocal active devices for quantum information processing applications.