4 papers
Measurement-Based Estimation of Causal Conditional Variances and Its Application to Macroscopic quantum phenomenon
Kosei Hatakeyama, Ryotaro Fukuzumi, Akira Matsumura +2
We analytically investigate a quantum estimation method for a mechanical oscillator in a detuned cavity system based solely on homodyne measurement records, building on the framewo…
Theoretical Study of the Squeezed-Light-Enhanced Sensitivity to Gravity-Induced Entanglement via Finite-Time Analysis
Kosei Hatakeyama, Daisuke Miki, Kazuhiro Yamamoto
We investigate the advantage of using squeezed input light for generating gravity-induced entanglement (GIE) through Fourier-domain analysis. Based on the findings of Ref.~\cite{Mi…
Momentum Squeezed State Realized via Optimal Filtering in Optomechanics: Implications for Gravity-Induced Entanglement
Ryotaro Fukuzumi, Kosei Hatakeyama, Daisuke Miki +1
We analyze the conditional quantum state of a mechanical mirror in an optomechanical system subject to continuous measurement, feedback control, and quantum filtering. We identify…
Space-based cm/kg-scale Laser Interferometer for Quantum Gravity
Nobuyuki Matsumoto, Katsuta Sakai, Kosei Hatakeyama +5
The experimental verification of the quantum nature of gravity represents a milestone in quantum gravity research. Recently, interest has grown for testing it via gravitationally i…