High Finesse Fiber Fabry-Perot Cavities: Stabilization and Mode Matching Analysis

Fiber Fabry-Perot cavities, formed by micro-machined mirrors on the end-facets of optical fibers, are used in an increasing number of technical and scientific applications, where they typically require precise stabilization of their optical resonances. Here, we study two different approaches to construct fiber Fabry-Perot resonators and stabilize their length for experiments in cavity quantum electrodynamics with neutral atoms. A piezo-mechanically actuated cavity with feedback based on the Pound-Drever-Hall locking technique is compared to a novel rigid cavity design that makes use of the high passive stability of a monolithic cavity spacer and employs thermal self-locking and external temperature tuning. Furthermore, we present a general analysis of the mode matching problem in fiber Fabry-Perot cavities, which explains the asymmetry in their reflective line shapes and has important implications for the optimal alignment of the fiber resonators. Finally, we discuss the issue of fiber-generated background photons. We expect that our results contribute towards the integration of high-finesse fiber Fabry-Perot cavities into compact and robust quantum-enabled devices in the future.Comment: The Supplemental Material is included in the source code of the article that can be downloaded from this arXiv page (see "Other formats"). Peer-reviewed version with changes to text and figure

Input-output relations for a 3-port grating coupled Fabry-Perot cavity

We analyze an optical 3-port reflection grating by means of a scattering matrix formalism. Amplitude and phase relations between the 3 ports, i.e. the 3 orders of diffraction are derived. Such a grating can be used as an all-reflective, low-loss coupler to Fabry-Perot cavities. We derive the input output relations of a 3-port grating coupled cavity and find distinct properties not present in 2-port coupled cavities. The cavity relations further reveal that the 3-port coupler can be designed such that the additional cavity port interferes destructively. In this case the all-reflective, low-loss, single-ended Fabry-Perot cavity becomes equivalent to a standard transmissive, 2-port coupled cavity

Optical vernier technique for in-situ measurement of the length of long Fabry-Perot cavities

We propose a method for in-situ measurement of the length of kilometer size Fabry-Perot cavities in laser gravitational wave detectors. The method is based on the vernier, which occurs naturally when the laser incident on the cavity has a sideband. By changing the length of the cavity over several wavelengths we obtain a set of carrier resonances alternating with sideband resonances. From the measurement of the separation between the carrier and a sideband resonance we determine the length of the cavity. We apply the technique to the measurement of the length of a Fabry-Perot cavity in the Caltech 40m Interferometer and discuss the accuracy of the technique.Comment: LaTeX 2e, 12 pages, 4 figure

Dynamic Resonance of Light in Fabry-Perot Cavities

The dynamics of light in Fabry-Perot cavities with varying length and input laser frequency are analyzed and the exact condition for resonance is derived. This dynamic resonance depends on the light transit time in the cavity and the Doppler effect due to the mirror motions. The response of the cavity to length variations is very different from its response to laser frequency variations. If the frequency of these variations is equal to multiples of the cavity free spectral range, the response to length is maximized while the response to the laser frequency is zero. Implications of these results for the detection of gravitational waves using kilometer-scale Fabry-Perot cavities are discussed

Experimental observation of cavity formation in composite metamaterials

Cataloged from PDF version of article.In this paper, we investigated one of the promising applications of left-handed metamaterials: composite metamaterial based cavities. Four different cavity structures operating in the microwave regime were constructed, and we observed cavity modes on the transmission spectrum with different quality factors. The effective permittivity and permeability of the CMM structure and cavity structure were calculated by use of a retrieval procedure. Subsequently, in taking full advantage of the effective medium theory, we modeled CMM based cavities as one dimensional Fabry-Perot resonators with a subwavelength cavity at the center. We calculated the transmission from the Fabry-Perot resonator model using the one-dimensional transfer matrix method, which is in good agreement with the measured result. Finally, we investigated the Fabry-Perot resonance phase condition for a CMM based cavity, in which the condition was satisfied at the cavity frequency. Therefore, our results show that it is possible to treat metamaterial based cavities as one-dimensional Fabry-Perot resonators with a subwavelength cavity. ©2008 Optical Society of America

Enhanced spontaneous emission from quantum dots in short photonic crystal waveguides

We report a study of the quantum dot emission in short photonic crystal waveguides. We observe that the quantum dot photoluminescence intensity and decay rate are strongly enhanced when the emission energy is in resonance with Fabry-Perot cavity modes in the slow-light regime of the dispersion curve. The experimental results are in agreement with previous theoretical predictions and further supported by three-dimensional finite element simulation. Our results show that the combination of slow group velocity and Fabry-Perot cavity resonance provides an avenue to efficiently channel photons from quantum dots into waveguides for integrated quantum photonic applications.Comment: 12 pages, 4 figure

Fiber-optic Based Fabry-Pérot Interferometry for High-resolution Motion Detection

I propose and demonstrate a highly-sensitive motion detection based on fiber Fabry-Perot interferometry with resolution below 100 nm. The interferometer is based on a fiber-optic collimator, specially designed for efficient signal back-coupling, and a discrete moving reflective mirror forming the Fabry-Perot cavity. To enhance the sensing range, I propose a dual-cavity fiber Fabry-Perot interferometer, the main idea based on the interference pattern of the two signals. Experimental results then showed that the proposed sensor is capable of sensing in a displacement range up to 1500 um with resolution of 2 nm and stability within a wide area of 2 mm. Furthermore, I evaluated the influence of the angular offset on FFPI performance.I propose and demonstrate a highly-sensitive motion detection based on fiber Fabry-Perot interferometry with resolution below 100 nm. The interferometer is based on a fiber-optic collimator, specially designed for efficient signal back-coupling, and a discrete moving reflective mirror forming the Fabry-Perot cavity. To enhance the sensing range, I propose a dual-cavity fiber Fabry-Perot interferometer, the main idea based on the interference pattern of the two signals. Experimental results then showed that the proposed sensor is capable of sensing in a displacement range up to 1500 um with resolution of 2 nm and stability within a wide area of 2 mm. Furthermore, I evaluated the influence of the angular offset on FFPI performance