Measurements of the phase shift on reflection for low-order infrared Fabry–Perot interferometer dielectric stack mirrors

Abstract

A simple technique based on a Fizeau interferometer to measure the absolute phase shift on reflection for a Fabry-Perot interferometer dielectric stack mirror is described. Excellent agreement between the measured and predicted phase shift on reflection was found. Also described are the salient features of low-order Fabry-Perot interferometers and the demonstration of a near ideal low-order (1-10) Fabry-Perot interferometer through minimizing the phase dispersion on reflection of the dielectric stack. This near ideal performance of a low-order Fabry-Perot interferometer should enable several applications such as compact spectral imagers for solid and gas detection. The large free spectral range of such systems combined with an active control system will also allow simple interactive tuning of wavelength agile laser sources such as CO(2) lasers, external cavity diode lasers, and optical parametric oscillators.

Optimization of Modulation Properties of Terahertz Metamaterial by Tuning Fabry–Pérot Resonances

“…To describe the transmission oscillations related with FPR we apply the formula which includes different reflectances and phase shifts at both sides of a dielectric slab [23]. For normally incident radiation transmittance of a MM sample can be given (2) where is the transmittance at FPR maximum, the coefficient of finesse can be expressed as (3) and the phase difference (4) Here and are the reflection coefficients from the front and rear interfaces, is the substrate thickness, is the radiation wavelength in free space, and is the phase shift on reflection from the front interface covered with SRRs.…”