collaborators

6 papers

hep-ph2025

Magnetic Helicity, Magnetic Monopoles, and Higgs Winding

Hajime Fukuda, Yuta Hamada, Kohei Kamada +2

Changes in magnetic helicity are often discussed across a variety of fields, from condensed matter physics to early universe cosmology. It is frequently stated that the helicity ch…

hep-ph2025

Background Suppression in Quantum Sensing of Dark Matter via Collective Entangled-State Projection

Shion Chen, Hajime Fukuda, Yutaro Iiyama +5

We show that measuring dark matter signal by projecting quantum sensors in the collective excited state can highly suppress the non-collective noise background, hence improving the…

hep-ex2025

Search for Dark Photon Dark Matter with a Mass around 36.1 μeV Using a Frequency-tunable Cavity Controlled through a Coupled Superconducting Qubit

Kan Nakazono, Shion Chen, Hajime Fukuda +10

We report the results of a search for dark photon dark matter using a cavity that employs a transmon qubit as a frequency tuner. The tuning mechanism utilizes the energy level shif…

quant-ph2024

Entanglement-enhanced AC magnetometry in the presence of Markovian noises

Thanaporn Sichanugrist, Hajime Fukuda, Takeo Moroi +5

Entanglement is a resource to improve the sensitivity of quantum sensors. In an ideal case, using an entangled state as a probe to detect target fields, we can beat the standard qu…

hep-ph2024

Non-thermal production of Higgsino dark matter by late-decaying scalar fields

Hajime Fukuda, Qiang Li, Takeo Moroi +1

We study the non-thermal production of the Higgsino dark matter (DM). Assuming that the lightest neutral Higgsino is the lightest supersymmetric particle (LSP) in minimal supersymm…

hep-ph2024

Leptogenesis from magnetic helicity of gauged

Hajime Fukuda, Kohei Kamada, Thanaporn Sichanugrist

If the symmetry is gauged with the addition of right-handed neutrinos, the standard model current is anomalous with respect to the gauge field itself. Then, the a…