516 research outputs found
Development of displacement- and frequency-noise-free interferometer in 3-D configuration for gravitational wave detection
The displacement- and frequency-noise-free interferometer (DFI) is a multiple
laser interferometer array for gravitational wave detection free from both the
displacement noise of optics and laser frequency noise. So far, partial
experimental demonstrations of DFI have been done in 2-D table top experiments.
In this paper, we report the complete demonstration of a 3-D DFI. The DFI
consists of four Mach-Zehnder interferometers with four mirrors and two
beamsplitters. The displacement noises both of mirrors and beamsplitters were
suppressed by up to 40 dB. The non-vanishing DFI response to a gravitational
wave was successfully confirmed using multiple electro-optic modulators and
computing methods
Demonstration of displacement-noise-free interferometry using bi-directional Mach–Zehnder interferometers
We have demonstrated displacement- and frequency-noise-free laser interferometry (DFI) by partially implementing a recently proposed optical configuration using bi-directional Mach–Zehnder interferometers (MZIs). This partial implementation, the minimum necessary to be called DFI, has confirmed the essential feature of DFI: the combination of two MZI signals can be carried out in a way that cancels the displacement noise of the mirrors and beam splitters while maintaining gravitational-wave signals. The attained maximum displacement noise suppression was 45 dB
The experimental plan of displacement- and frequency-noise free laser interferometer
We present the partial demonstration of displacement- and laser-noise free interferometer (DFI) and the next experimental plan to examine the complete configuration. A part of the full implementation of DFI has been demonstrated to confirm the cancellation of beamsplitter displacements. The displacements were suppressed by about two orders of magnitude. The aim of the next experiment is to operate the system and to confirm the cancellation of all displacement noises, while the gravitational wave (GW) signals survive. The optical displacements will be simulated by electro-optic modulators (EOM). To simulate the GW contribution to laser lights, we will use multiple EOMs
The Experimental plan of the 4m Resonant Sideband Extraction Prototype for The LCGT
The 4m Resonant Sideband Extraction (RSE) interferometer is a planned prototype of the LCGT interferometer. The aim of the experiment is to operate a powerrecycled Broadband RSE interferometer with suspended optics and to achieve diagonalization of length signals of the central part of the interferometer directly through the optical setup. Details of the 4m RSE interferometer control method as well as the design of the experimental setup will be presented
Displacement noise free interferometory for gravitational wave detection
We have demonstrated displacement- and frequency-noise-free laser interferometry (DFI) by partially implementing a recently proposed optical configuration using bidirectional Mach-Zehnder interferometers (MZIs). This partial implementation, the minimum necessary to be called DFI, has confirmed the essential feature of DFI: the combination of two MZI signals can be carried out in a way that cancels displacement noise of the mirrors and beam splitters while maintaining gravitational-wave signals. The attained maximum displacement noise suppression was 45 dB
Downselect of the signal extraction scheme for LCGT
Large Cryogenic Gravitational wave Telescope (LCGT) is the future Japanese gravitational-wave detector. It will employ the broadband resonant sideband extraction (RSE) as its optical configuration. We compared four signal extraction schemes that have been proposed so as to downselect one of them as the scheme for LCGT. The selected scheme uses the phase and amplitude modulation sidebands: the phase modulation sidebands transmitting to the antisymmetric port (AP) and the amplitude modulation sidebands reffected to the symmetric port (SP) by the functions of the Michelson asymmetry. Using these sidebands, a new technique called 'delocation' is applicable. One advantage is that the control signals of the undesired signals do not appear at the AP, where the differential signals appear
Demonstration of displacement- and frequency-noise free laser interferometry using bi-directional Mach-Zehnder interferometers
We have demonstrated displacement- and frequency-noise free laser interferometry (DFI) by partially implementing a recently proposed optical configuration using bi-directional Mach-Zehnder interferometers (MZI). This partial implementation, the minimum necessary to be called DFI, has confirmed the essential feature of DFI: the combination of two MZI signals can be carried out in a way which cancels displacement noise of the mirrors while maintaining gravitational wave signals. The attained maximum displacement noise suppression allowed a simulated-SNR of 45dB
Review of the Laguerre-Gauss mode technology research program at Birmingham
Gravitational wave detectors from the advanced generation onwards are
expected to be limited in sensitivity by thermal noise of the optics, making
the reduction of this noise a key factor in the success of such detectors. A
proposed method for reducing the impact of this noise is to use higher-order
Laguerre-Gauss (LG) modes for the readout beam, as opposed to the currently
used fundamental mode. We present here a synopsis of the research program
undertaken by the University of Birmingham into the suitability of LG mode
technology for future gravitational wave detectors. This will cover our
previous and current work on this topic, from initial simulations and table-top
LG mode experiments up to implementation in a prototype scale suspended cavity
and high-power laser bench
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