A Near Quantum Limited Sub-GHz TiN Kinetic Inductance Traveling Wave Parametric Amplifier Operating in a Frequency Translating Mode

TL;DR

This paper reports the design and experimental testing of a TiN-based kinetic inductance traveling-wave parametric amplifier operating at sub-GHz frequencies, achieving high gain with low pump power in a frequency translating mode.

Contribution

It introduces a compact TiN microstrip design for sub-GHz amplification with significantly reduced pump power compared to previous NbTiN-based devices.

Findings

Achieved up to 22 dB gain from 450 to 850 MHz.

Reduced pump power requirement by roughly an order of magnitude.

Demonstrated effective frequency translating operation.

Abstract

We present the design and experimental characterization of a kinetic-inductance traveling-wave parametric amplifier (KI-TWPA) for sub-GHz frequencies. KI-TWPAs amplify signals through nonlinear mixing processes supported by the nonlinear kinetic inductance of a superconducting transmission line. The device described here utilizes a compactly meandered TiN microstrip transmission line to achieve the length needed to amplify sub-GHz signals. It is operated in a frequency translating mode where the amplified signal tone is terminated at the output of the amplifier, and the idler tone at approximately 2.5~GHz is brought out of the cryostat. By varying the pump frequency, a gain of up to 22 dB was achieved in a tunable range from about 450 to 850~MHz. Use of TiN as the nonlinear element allows for a reduction of the required pump power by roughly an order of magnitude relative to NbTiN, which has been used for previous KI-TWPA implementations. This amplifier has the potential to enable high-sensitivity and high-speed measurements in a wide range of applications, such as quantum computing, astrophysics, and dark matter detection.