Quantum-Mechanical Radiation-Pressure Fluctuations in an Interferometer

ABSTRACT An analysis of two-dimensional viscous, radiation hydrodynamic numerical simulations of thin α-discs around a stellar mass black hole reveals multiple robust, coherent oscillations. Our disc models are initialized on both the gas- and radiation-pressure-dominated branches of the thermal equilibrium curve, with mass accretion rates between $\dot{M} = 0.01 L_\mathrm{Edd}/c^2$ and $10\, L_\mathrm{Edd}/c^2$. In the initially radiation-pressure-dominated disc, we confirm the presence of global inertial–acoustic oscillations of frequency slightly above the maximum radial epicyclic one. In the gas-pressure-dominated Schwarzschild-metric models, we find a velocity oscillation occurring at the maximum value of the radial epicyclic frequency, $3.5\times 10^{-3}\, t_\mathrm{g}^{-1}$, which is most likely a trapped fundamental g-mode. For the Kerr-metric, gas-pressure-dominated disc with dimensionless black hole spin parameter a* = 0.5, the mode frequency is well below the epicyclic frequency maximum, thus confirming that this oscillation is a trapped g-mode. Additionally, the total pressure fluctuations in the discs strongly suggest standing-wave p-modes with frequencies below the apparent g-mode frequency, some trapped in the inner disc close to the innermost stable circular orbit (ISCO), others present in the middle/outer parts of the disc. The strongest oscillations occur at the breathing oscillation frequency and are present in all the numerical models we report here, as are weaker velocity oscillations at the vertical epicyclic frequencies. The vertical oscillations show a 3:2 frequency ratio with oscillations occurring approximately at the radial epicyclic frequency, which could be of astrophysical importance in systems with observed twin peak, high-frequency quasi-periodic oscillations.

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Quantum theory of radiation-pressure fluctuations on a mirror

Physical Review A ◽

10.1103/physreva.51.2726 ◽

1995 ◽

Vol 51 (4) ◽

pp. 2726-2737 ◽

Cited By ~ 13

Author(s):

P. Samphire ◽

R. Loudon ◽

M. Babiker

Keyword(s):

Quantum Theory ◽

Radiation Pressure ◽

Pressure Fluctuations ◽

Quantum Theory Of Radiation

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Quantum mechanical representation of acoustic streaming and acoustic radiation pressure

Physical Review E ◽

10.1103/physreve.64.026311 ◽

2001 ◽

Vol 64 (2) ◽

Cited By ~ 17

Author(s):

Masanori Sato ◽

Toshitaka Fujii

Keyword(s):

Radiation Pressure ◽

Acoustic Radiation ◽

Acoustic Streaming ◽

Quantum Mechanical ◽

Acoustic Radiation Pressure ◽

Quantum Mechanical Representation

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Thermal noise study of a radiation pressure noise limited optical cavity with fused silica mirror suspensions

The European Physical Journal D ◽

10.1140/epjd/e2020-10183-7 ◽

2020 ◽

Vol 74 (11) ◽

Author(s):

Sibilla Di Pace ◽

Luca Naticchioni ◽

Martina De Laurentis ◽

Flavio Travasso

Keyword(s):

Gravitational Wave ◽

Radiation Pressure ◽

Thermal Noise ◽

Optical Cavity ◽

Pressure Fluctuations ◽

Fused Silica ◽

Optical Cavities ◽

Quantum Radiation ◽

Interferometric Detectors ◽

High Finesse

Abstract In this work we study the thermal noise of two monolithically suspended mirrors in a tabletop high-finesse optical cavity. We show that, given suitable seismic filters, such a cavity can be designed to be sensitive to quantum radiation pressure fluctuations in the audio band of gravitational wave interferometric detectors below 1 kHz. Indeed, the thermal noise of the suspensions and of the coatings constitutes the main limit to the observation of quantum radiation pressure fluctuations. This limit can be overcome with an adequate choice of mirror suspension and coating parameters. Finally, we propose to combine two optical cavities, like those modeled in this work, to obtain a tabletop quantum radiation pressure-limited interferometer. Graphical abstract

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