Optical Demonstration of THz, Dual-Polarization Sensitive Microwave Kinetic Inductance Detectors

TL;DR

This paper demonstrates dual-polarization sensitive microwave kinetic inductance detectors (MKIDs) at 250 μm, advancing detector technology for suborbital balloon experiments aiming to map polarized dust emission.

Contribution

First demonstration of dual-polarization sensitive MKIDs at 250 μm, enabling improved polarization measurements in astrophysical observations.

Findings

Achieved photon-noise-limited sensitivity in dual-polarization MKIDs

Successfully fabricated monolithic arrays for multiple wavebands

Demonstrated dual-polarization sensitivity in the 250 μm band

Abstract

The next generation BLAST experiment (BLAST-TNG) is a suborbital balloon payload that seeks to map polarized dust emission in the 250 $\mu$m, 350 $\mu$m and 500 $\mu$m wavebands. The instrument utilizes a stepped half-wave plate to reduce systematics. The general requirement of the detectors is that they are photon-noise-limited and dual-polarization sensitive. To achieve this goal, we are developing three monolithic arrays of cryogenic sensors, one for each waveband. Each array is feedhorn-coupled and each spatial pixel consists of two orthogonally spaced polarization-sensitive microwave kinetic inductance detectors (MKIDs) fabricated from a Ti/TiN multilayer film. In previous work, we demonstrated photon-noise-limited sensitivity in 250 $\mu$m waveband single polarization devices. In this work, we present the first results of dual-polarization sensitive MKIDs at 250 $\mu$m.