Accurate Gouy phase measurement in an astigmatic optical cavity

Abstract

We present measurements of the Gouy phase accumulation for the fundamental mode of an astigmatic Fabry-Perot cavity over 70 % of its stability range. The method is based on simultaneous measurement of the resonant frequencies of the fundamental mode and the TEM 11 Hermite-Gauss mode of the cavity. We achieve an uncertainty of 2:7 Â 10 À6 rad, which, in the context of displacement metrology, is sufficient to enable measurements over 50 mm with relative uncertainty below 10 À10 .

An Initial Reproduction of SI Capacitance Unit From a New Calculable Capacitor at NIM

“…Further investigations are necessary. After analyzing the finished work, the following points are proposed: 1) to apply the electrical compensation method instead of the current nosepiece and to reduce the measurement standard deviation down to the level of 10 −9 ; 2) to raise the accuracy of capacitance measurement; 3) to improve the laser length measurement, including the Gouy phase effect [24], [25]; 4) to estimate further the contribution of the uncertainty factors, such as voltage, frequency, lateral displacement, and long-term stability.…”

Gouy phase shift measurement in a high-finesse cavity by optical feedback frequency locking

“…To the best of our knowledge, state of the art measurements of Gouy phase shifts were performed by Durand et al, achieving a 2.7 × 10 −6 rad accuracy and 6 × 10 −7 rad precision with 10 s measurements [10]. Their setup involved three narrow-linewidth fiber lasers independently locked to different resonances of a high finesse cavity (F = 20 000) by using the standard Pound-Drever-Hall (PDH) technique, requiring electro-optic modulators.…”

Laguerre–Gaussian vortex mode generation from astigmatic semiconductor microcavity

“…[17][18][19][20] In this paper, we demonstrate that an alternative approach based on the astigmatism of the microcavity successfully generates LG  0 1 vortex modes from a conventional broad-area VCSEL. We utilize an optical injection technique, which is used to investigate the cavity resonances, 25,26) to investigate the transverse cavity modes of the VCSEL, where we promote the injection beams with various transverse modes for the excitation. In particular, we show that the HG beam injection enables LG mode generation, allowing a reduction of the symmetrical requirements of the cavity and thus extending the flexibility in design and fabrication of the vortex lasers.…”

“…Figure 1(a) shows a schematic view of the experimental setup. The transverse mode properties were investigated using an optical injection technique, 25,26) where we employed commercially available broad-area VCSELs (single longitudinal mode operation at a wavelength of 780 nm) as both master and slave lasers. Each VCSEL consisted of 3 Al 0.12 Ga 0.88 As/Al 0.30 Ga 0.70 As quantum wells between two distributed Bragg reflectors for λ-cavity and had a large aperture size (∼10 μm in diameter) that was responsible for generating higher-order transverse modes.…”

“…In the HG modes, the lift of the degeneracy is clearly visible, indicating the presence of the residual astigmatism of the VCSEL cavity. 25) In this case, the HG resonances are assigned to the orthogonal HG modes (HG x and HG y ) associated with the principal axes of the astigmatism. By using corresponding astigmatic Gouy phases f x G and f y G , Eq.…”