相关论文: A polarisation modulation scheme for measuring vac…
Vacuum magnetic birefringence was predicted long time ago and is still lacking a direct experimental confirmation. Several experimental efforts are striving to reach this goal, and the sequence of results promises a success in the next few…
We present an experimental systematics study of the polarimetric method for measuring the vacuum magnetic birefringence based on a pair of rotating half-wave plates. The presence of a systematic effect at the same frequency as the sought…
A new Compton longitudinal polarimeter currently under construction for HERA is presented. The key component of the polarimeter is a Fabry-Perot cavity located around the electron beam pipe. With such an optical cavity, a continuous laser…
A Fabry-Perot cavity polarimeter, installed in 2003 at HERA for the second phase of its operation, is described. The cavity polarimeter was designed to measure the longitudinal polarisation of the HERA electron beam with high precision for…
We argue that measurements of X-ray polarization using the recently launched Imaging X-ray Polarimetry Explorer will answer many open questions about magnetars in particular the physical state of their surfaces, whether vacuum birefringence…
A precise and fast Fabry-Perot cavity polarimeter, installed in the HERA tunnel in the summer of 2003, was used to measure the longitudinal polarisation of the lepton beam. A complete theoretical model has been developed in order to control…
We introduce a laser heterodyne polarimeter designed for the precision measurement of sub $\mu\mathrm{rad}$ differential phase shifts due to birefringence. The polarimeter will be used in an initial testbed for a potential future vacuum…
Although experimental efforts have been active for about 30 years now, a direct laboratory observation of vacuum magnetic birefringence, an effect due to vacuum fluctuations, still needs confirmation. Indeed, the predicted birefringence of…
Optical Fabry-Perot cavities always show a non-degeneracy of two orthogonal polarisation states. This is due to the unavoidable birefringence of dielectric mirrors whose effects are extremely important in Fabry-Perot based high-accuracy…
A new experiment to measure vacuum magnetic birefringence (VMB), the OVAL experiment, is reported. We developed an original pulsed magnet that has a high repetition rate and applies the strongest magnetic field among VMB experiments. The…
A measurement of the longitudinal polarization of the electron beam at HERA utilizing coherent interactions of high energy photons in crystals is proposed. Modification of existing facilities would allow an independent polarization…
Probing vacuum structures deformed by high intense fields is of great interest in general. In the context of quantum electrodynamics (QED), the vacuum exposed by a linearly polarized high-intensity laser field is expected to show…
We present the current status and outlook of the optical characterization of the polarimeter at the Bir\'{e}fringence Magn\'etique du Vide (BMV) experiment. BMV is a polarimetric search for the QED predicted anisotropy of vacuum in the…
We discuss the experimental techniques used to date for measuring the changes in polarization state of a laser produced by a strong transverse magnetic field acting in a vacuum. We point out the likely artifacts that can arise in such…
A ring-laser experiment, similar to the Canterbury ring laser, to detect axion- and {\sc qed}-induced vacuum birefringence is proposed. It uses a slowly modulated magnetic field and a novel polarization geometry. Both axion coupling and…
In this work we present data characterizing the sensitivity of the Bir\'{e}fringence Magnetique du Vide (BMV) instrument. BMV is an experiment attempting to measure vacuum magnetic birefringence (VMB) via the measurement of an ellipticity…
The measurement of vacuum polarisation effects, in particular vacuum birefringence, using combined optical and x-ray laser pulses is now actively pursued. Here we briefly examine the feasibility of two alternative setups. The first utilises…
In this work, we propose polarimetry experiments to search for low-mass (sub-eV) bosonic field dark matter, including axions and axion-like particles. We show that a polarimetry configuration consisting of a thick birefringent solid inside…
We describe the principle and the status of the PVLAS experiment which is presently running at the INFN section of Ferrara, Italy, to detect the magnetic birefringence of vacuum. This is related to the QED vacuum structure and can be…
In a recent paper it is claimed that vacuum birefringence has been experimentally observed for the first time by measuring the degree of polarization of visible light from a Magnetar candidate, a neutron star with a magnetic field…