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A Fabry-Perot etalon with a finesse of 100 000 is used as a photonic filter in a single loop optoelectronic oscillator. The etalon provides narrow bandwidth microwave filtering at harmonics of its 1.5 GHz free spectral range for oscillation in the range of 6 to 60 GHz. Fiber delays as long as 2 km are added to the loop with no spurious modes visible above the noise floor. The environmental stability of the etalon makes it suitable as a secondary reference for feedback to the optical frequency which contributes to the reduction of phase noise and long term frequency drift.

A slab-coupled optical waveguide amplifier (SCOWA) is used to construct a 10-GHz harmonically modelocked laser with an intra-cavity etalon that serves as a high-finesse spectral filter. The laser output is a frequency comb that is actively stabilized to the transmission peaks of the etalon through a Pound-Drever-Hall scheme. The linewidth of the individual comb-lines is ~1 kHz and the frequency instability

A frequency comb is used as a set of coherent local oscillators to downconvert and spectrally compress white light that has been periodically filtered by a Fabry–Perot etalon. Multiheterodyne detection allows white light spread across 100 GHz of optical spectrum to be compressed to 5 GHz of radio frequency (RF) bandwidth for electronic sampling on an oscilloscope. Correlations are observed at delays of up to 20 km with a minimum resolution of less than 1 mm. Calculations show that resolution may be easily increased by increasing etalon finesse and frequency comb bandwidth.

Optical frequency combs are used as local oscillators for the measurement and analysis of unknown optical waveforms with periodic time domain structures. Experimental results obtained by heterodyning pulsed and phase-modulated laser sources are presented. The analysis is then extended to the heterodyning and sampling of bandlimited incoherent light sources. It is shown theoretically and experimentally that the correlations between photodetected white light at different times can generate RF interference that is sensitive to the optical phase.

A 100,000 finesse Fabry-Perot etalon with a 1.5 GHz free spectral range is used as a photonic filter in an optoelectorinc oscillator. The etalon acts as a ~15 kHz microwave filter to suppress spurious modes in a single loop OEO configuration. The etalon maintains its narrow filtering capability at harmonics of the FSR. Phase noise of the 10.5 GHz tone with 2 km of delay is measured at -120 dBc/Hz at 10 kHz offset. Oscillation as high as 54 GHz with 3 km of fiber delay is achieved while maintaining suppression of spurious modes below the noise floor of the measurement. Pound-Drever-Hall frequency stabilization of the laser frequency is used to reduce optical frequency noise and keep the laser frequency centered within the etalon resonance for long term operation of the OEO.

A Fabry-Perot etalon with 1.498 GHz free spectral range and 100,000 finesse is used for photonic filtering in an optoelectronic oscillator. Oscillations at multiples of its FSR are produced at 10.49 GHz and 50.9 GHz.

A Fabry-Perot etalon with 1.498 GHz free spectral range is used for photonic filtering in an optoelectronic oscillator. Oscillations at multiples of its FSR are produced at 10.49 GHz, 36.0 GHz, and 53.9 GHz.

Parabolic spectral filtering and interferometric spectral phase compensation was implemented in a real-time feedback loop for high power fiber CPA system, resulting in near transform limited sub-picosecond pulses and 4.5 times increase in peak power

In the Spring Semester of 2011, Univ. of Central Florida's CREOL introduced an elective course in Optomechanical Design. In addition to homework assignments and exams, one component of the course grade was a design project. Rather than the traditional "assigned" project, the instructor experimented with a novel research-centric approach. Specifically, students were asked to select a project directly applicable to their graduate research. While challenging for the instructor to grade, student motivation and performance remained exceptionally high throughout the semester. This paper summarizes the background, projects, and pedagogical benefits of such a research-centric approach to project-based learning.

In this paper, we show recent results in the use of stabilized optical frequency combs from mode-locked diode lasers operating in the telecommunication C-band for applications in coherent parallel signal processing architectures [1]. For selecting and modulating single components within the frequency comb, novel approaches that rely on the properties of injection locked oscillators will be used. These approaches will show that one can simultaneously select single components from a frequency comb and realize either modulation or detection functionality. To demonstrate how stabilized frequency combs can be used in a coherent signal processing scenario, we use the frequency combs and injection locked microcavity lasers to perform real time waveform generation, measurement, and matched filtering.

A tunable optoelectronic oscillator using a high finesse etalon as both a photonic filter and optical frequency reference is presented. The microwave tone at 10.487 GHz displays fractional frequency instability of 3.3×10−10 at 1 s.

Multiheterodyne detection is a particularly effective method in spectroscopy and metrology to measure the full, complex spectrum of an unknown signal [1,2]. Upon photodetection, the mixing of two optical frequency combs (OFCs) with different mode spacings produces a frequency comb in the radio frequency (RF) domain which retains the amplitude and phase information of both OFCs [3]. If one of the two OFCs acts as a reference with flat spectral phase, the spectral phase of the RF comb directly mirrors that of the test comb, which can then be mapped to the optical spectrum and Fourier transformed to produce the comb's time-domain waveform [4]. Recently, it has been demonstrated that by considering a larger portion of the RF comb, a self-referenced measurement of each optical comb can be recovered, thus eliminating the need for a known reference with flat phase [5]. In this manuscript, a more general form of this technique is explored, in which the mode spacings of the two unknown comb sources are detuned from each other by a factor of two or greater. This is a case of interest, seeing as how arbitrary waveforms generated from spectral modulation of OFCs which one might wish to characterize regularly exceed 10's of GHz rates, whereas the self-referenced, carrier-envelope offset stabilized sources which provide absolute knowledge of the optical frequencies involved in the multiheterodyne process are most commonly found in the sub-GHz repetition rate regime.

Low noise microwave signals are important for many applications in communications, radar, and navigation. The optoelectronic oscillator (OEO) design allows for creation of stable signals by taking advantage of optical elements for their long energy storage time and very low loss. High-Q elements include long fiber delay lines [1] and photonic filters [2] such as Fabry-Perot etalons (FPE) and whispering gallery mode resonators. Photonic filters also serve as mode selectors for the RF oscillation frequency, eliminating the need for RF bandpass filters which eliminate higher harmonic oscillations. Presented here is an optoelectronic oscillator system utilizing a high finesse FPE for both a photonic filter and optical frequency reference. By referencing the laser source to the etalon through Pound-Drever-Hall (PDH) frequency stabilization, a narrow linewidth, long term stable optical source is created [3], reducing output frequency drifts due to the source. The RF output of the OEO shows fractional frequency instability of 3.3×10−10 at 1 s. This result displays an improvement of more than two orders of magnitude over previous results using photonic filtering with a lower finesse etalon[4].

We present a method to independently measure the spectral phase of an optical frequency comb by heterodyning it with a second comb of arbitrarily detuned repetition rate and appropriately processing the resulting electrical frequency comb.

A 0.39 W, 10 GHz MOPA system based on Slab-Coupled Optical Waveguide Amplifiers (SCOWAs) is presented. The output pulse-train timing jitter (∼6 fs), amplitude noise (∼0.03%) and spectral bandwidth exhibit no visible degradation.

Multi-heterodyne mixing of an optical frequency comb with white light filtered by a Fabry-Perot etalon is used to measure white light cross-correlations at a distance of 13 meters with a resolution of 10 ps.

We present an etalon-stabilized mode-locked laser with 10 GHz combline-to-combline spacing featuring a novel cavity design and the application of said comb-sources in multi-heterodyne detection. These frequency combs can be used as local oscillators for the measurement and analysis of arbitrary optical waveforms with periodic time domain structures. Experimental results obtained by heterodyning pulsed and phase modulated laser sources are presented.

We characterize the properties of a 100 MHz fiberized etalon. Sub-Hz (10−8) precision is attained for the FSR measurement for both polarization eigenstates. The finesse is measured with 3 % precision and the acoustic noise frequency response of the etalon is experimentally measured.

In this work a narrow linewidth (1 kHz) laser source is used to measure the free spectral range of a fiberized Fabry-Perot etalon with sub-Hz accuracy (10(-8)). A previously demonstrated technique based on the Pound-Drever-Hall error signal is improved in accuracy by the use of a narrow linewidth laser swept in frequency via an acousto-optic modulator, or single sideband generation. The sub-Hz (10(-8)) accuracy attained enables the characterization of both the long-term drift and the polarization dependence of the free spectral range of the fiberized etalon.

This work presents group delay measurements for a 1.3 μm quantum dot semiconductor optical amplifier at various injection currents. White-light interferometry is used to obtain group delay data spanning both ground state and first excited state transitions, ranging from 1200 nm to 1320 nm. The group delay, group velocity dispersion and existence of higher order dispersion is observed and quantified.

Spectral interferometry is used to measure the dispersion of a quantum dot semiconductor optical amplifier under various injection current values in the wavelength range of 1200 to 1340 nm, spanning ground and first excited state.

A Fabry-Perot etalon is inserted into a semiconductor-based laser cavity operating at the chirped pulse amplification regime. The laser output exhibits supermode noise spur suppression and a semiconductor-based optical frequency comb is generated.

Measurement of the FSR of an etalon having finesse of 1000 with 7 digits of accuracy or 2.5 kHz. A modified PDH technique is used in conjunction with a frequency swept, narrow-linewidth CW laser.