activity
20242026
collaborators

5 papers

physics.atom-ph2026

Analytical and numerical studies of periodic superradiance

Hideaki Hara, Yuki Miyamoto, Junseok Han +6

We conduct a theoretical study to understand the periodic superradiance observed in an Er:YSO crystal. First, we construct a model based on the Maxwell-Bloch equations for a reduce…

physics.atom-ph2026

Control of emission interval and timing in triggered periodic superradiance

Hideaki Hara, Riku Omoto, Noboru Sasao +6

To achieve more controllable development of coherence in solids, we investigated the effect of a trigger laser tuned to the superradiance transition wavelength on periodic superrad…

astro-ph.CO2025

Observational tests for a class of scalar-tensor gravity

Kunio Kaneta, Kin-ya Oda, Motohiko Yoshimura

We study observational bounds in a class of scalar-tensor gravity theories recently proposed. Either an upper or lower bound on a conformal factor in these theories is derived from…

hep-ph2025

A common origin of two accelerating universes: inflation and dark energy

Kunio Kaneta, Kin-ya Oda, Motohiko Yoshimura

We develop a quantum theory of inflaton and its decay product of various gauge boson pairs to investigate the preheating towards thermalized universe. The inflaton decay into gauge…

hep-ph2024

Parametrically amplified super-radiance towards hot big bang universe

Motohiko Yoshimura, Kunio Kaneta, Kin-ya Oda

We propose a mechanism of preheating stage after inflation, using a new idea of parametrically amplified super-radiance. Highly coherent state, characterized by macro-coherence of…