We demonstrate very high resolution photon spectroscopy with a microwave-multiplexed two-pixel transition-edge sensor (TES) array. We measured a 153Gd photon source and achieved an energy resolution of 63 eV full-width-at-half-maximum at 97 keV and an equivalent readout system noise of 86 pA/Hz at the TES. The readout circuit consists of superconducting microwave resonators coupled to radio-frequency superconducting-quantum-interference-devices (SQUID) and transduces changes in input current to changes in phase of a microwave signal. We use flux-ramp modulation to linearize the response and evade low-frequency noise. This demonstration establishes one path for the readout of cryogenic X-ray and gamma-ray sensor arrays with more than 103 elements and spectral resolving powers R=λ/Δλ>103.
@article{arxiv.1310.7287,
title = {High-resolution gamma-ray spectroscopy with a microwave-multiplexed transition-edge sensor array},
author = {Omid Noroozian and John A. B. Mates and Douglas A. Bennett and Justus A. Brevik and Joseph W. Fowler and Jiansong Gao and Gene C. Hilton and Robert D. Horansky and Kent D. Irwin and Zhao Kang and Daniel R. Schmidt and Leila R. Vale and Joel N. Ullom},
journal= {arXiv preprint arXiv:1310.7287},
year = {2015}
}
Comments
5 pages, 5 figures, to be published in Applied Physics Letters, Vol 103, Issue 20, on 11-Nov-2013