Mach–Zehnder fiber interferometer test of the anisotropy of the speed of light

Abstract

Abstract. Two optical fiber Mach-Zehnder interferometers were constructed in an environment with a temperature stabilization of better than 1 mK per day. One interferometer with a length of 12 m optical fiber in each arm with the main direction of the arms perpendicular to each other. Another with a length of 2 m optical fiber in each arm where the main direction of the arms are parallel as a control. In each arm 1 m of fiber was wound around a ring made of piezo material enabling the control of the length of the arms by means of a voltage. The influence of the temperature on the optical phase difference between the interferometer arms was measured. It is attributed to the temperature change induced variation of the interaction region of the optical fiber couplers. Further, the influence of rotation of the interferometers at the Earth surface on the observed phase differences was determined. For one interferometer (with the long and perpendicular arms) it was found that the phase difference depends on the azimuth of the interferometer. For the other one (with the short and parallel arms) no relevant dependence on the azimuth has been measured.PACS. 03.30.+p Special relativity -06.30.-k Measurements common to several branches of physics and astronomy -42.25.Bs Wave propagation, transmission and absorption

Experiments to test special relativity

“…The results are described in [14,15]. Although a first and second order signal was observed, the sidereal dependence is absent.…”

“…The detector was used in a set-up where the phase difference between two arms of a Mach-Zehnder interferometer was compared with the phase of the standing wave. The set-up was rotated and data treatment was similar as described in [14,15]. Upon rotation of the set-up the phase difference revealed a first order effect, the amplitude and azimuth of which are shown in figure 1.…”

“…During the measurements the transmission of the cavities was kept minimal by means of adaptation of the cavity length by piezo-crystals. The set-up was rotated and data treatment was similar as described in [14,15]. Upon rotation of the set-up the phase difference revealed a first order effect, the amplitude and azimuth of which are shown in figure 3.…”

Asymmetric Mach–Zehnder fiber interferometer test of the anisotropy of the speed of light

“…11.With an asymmetric fiber Mach-Zehnder interferometer (see Fig. 1) the light, injected into a fiber by means of a laser, is split into two equal and in-phase parts by a 2 Â 2 directional coupler.…”

“…It could also be due to transmission or polarization effects as discussed in ref. 11. The temperature control was the same as described in ref.…”