Quantum-enhanced Search for Galactic Dark Photons Using Cat-State Cavities
Abstract
We present a quantum-enhanced search for the Galactic dark-photon background (GDPB), a relativistic and anisotropic vector field that can be produced by dark-matter decay or annihilation in the Milky Way halo. We reinterpret an existing quantum-enhanced dark-photon dataset obtained with a superconducting circuit QED platform originally developed for wave-like dark-photon dark-matter searches, consisting of a high-Q niobium cavity in the TM010 mode dispersively coupled to a transmon qubit. By preparing four-component cat states and performing repeated quantum non-demolition parity measurements, analyzed with a hidden Markov model, we extract photon-transition probabilities for multiple cat amplitudes and integration times. The coupling to the GDPB is governed by a polarization- and angle-dependent cavity overlap function, which predicts a distinctive diurnal modulation of the excitation rate for both longitudinal and transverse polarizations. From the absence of such modulation, we set 90\% confidence-level bounds on the kinetic-mixing parameter ε for two benchmark production mechanisms (parametric and cascade decay) over the relativistic mass range mX ≪ ωc.
Related
- Constraints on Galactic Dark Photons from a DALI Prototype
- Search for long-lived dark photons from hidden radiation at the LHC
- Search for dark photons from Higgs boson decays in the gluon-gluon fusion channel in proton-proton collisions at √s=13.6 TeV with the ATLAS detector
- Topology-optimized dielectric cavities for enhanced excitonic light emission from WSe2
- Search for dark photons from Higgs boson decays in the gluon-gluon fusion channel in proton-proton collisions at √s=13.6 TeV with the ATLAS detector
BibTeX
@misc{wang2026quantumenhanced,
title = {{Quantum-enhanced Search for Galactic Dark Photons Using Cat-State Cavities}},
author = {Aoying Wang and Yanjie Zeng and Yanyan Cai and Jing Shu and Bin Xu and Yuan Xu and Pan Zheng},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.19751},
eprint = {2610.19751},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.19751},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Quantum-enhanced Search for Galactic Dark Photons Using Cat-State Cavities
AU - Aoying Wang
AU - Yanjie Zeng
AU - Yanyan Cai
AU - Jing Shu
AU - Bin Xu
AU - Yuan Xu
AU - Pan Zheng
PY - 2026
DA - 2026/10/14
PB - arXiv
DO - 10.48550/arxiv.2610.19751
UR - https://arxiv.org/abs/2610.19751
AB - We present a quantum-enhanced search for the Galactic dark-photon background (GDPB), a relativistic and anisotropic vector field that can be produced by dark-matter decay or annihilation in the Milky Way halo. We reinterpret an existing quantum-enhanced dark-photon dataset obtained with a superconducting circuit QED platform originally developed for wave-like dark-photon dark-matter searches, consisting of a high-Q niobium cavity in the TM_010 mode dispersively coupled to a transmon qubit. By preparing four-component cat states and performing repeated quantum non-demolition parity measurements, analyzed with a hidden Markov model, we extract photon-transition probabilities for multiple cat amplitudes and integration times. The coupling to the GDPB is governed by a polarization- and angle-dependent cavity overlap function, which predicts a distinctive diurnal modulation of the excitation rate for both longitudinal and transverse polarizations. From the absence of such modulation, we set 90\% confidence-level bounds on the kinetic-mixing parameter ε for two benchmark production mechanisms (parametric and cascade decay) over the relativistic mass range m_X ≪ ω_c.
ER -