Absolute distance measurement with a gain-switched dual optical frequency comb.

The measurement of distance plays an important role in many aspects of modern societies. In this paper, an absolute distance measurement method for arbitrary distance is proposed and demonstrated using mode-resolved spectral interferometry with a gain-switched dual comb. An accuracy of 12 µm, when compared to a He-Ne fringe counting laser interferometer, for a displacement up to 2.

Integrated dual optical frequency comb source.

A monolithically integrated dual-channel optical frequency comb source is demonstrated in this paper. Three lasers are integrated on a single chip using a regrowth-free fabrication process in a master-slave-slave configuration. The master laser's power is split equally using a 1x2 multimode interference coupler and injection locks the two slave lasers.

Off-Axis Cavity-Enhanced Absorption Spectroscopy of NH in Air Using a Gain-Switched Frequency Comb at 1.514 μm.

A custom-designed gain-switched frequency comb (GSFC) source was passively coupled to a medium finesse ( ≈ 522) cavity in off-axis configuration for the detection of ammonia (NH) in static dry air. The absorption of ammonia was detected in the near infrared spectral region between 6604 and 6607 cm using a Fourier transform detection scheme. More than 30 lines of the GSFC output (free spectral range 2.

Expansion and phase correlation of a wavelength tunable gain-switched optical frequency comb.

A novel scheme for the expansion and phase correlation of a wavelength tunable gain-switched optical frequency comb (OFC) is presented. This method entails firstly combining two gain-switched OFCs and expanding them using a phase modulator. Subsequently, the phase correlation between all the comb lines is induced through four-wave mixing (FWM) in a semiconductor optical amplifier (SOA).

Polarization insensitive all-optical wavelength conversion of polarization multiplexed signals using co-polarized pumps.

We study and experimentally validate the vector theory of four-wave mixing (FWM) in semiconductor optical amplifiers (SOA). We use the vector theory of FWM to design a polarization insensitive all-optical wavelength converter, suitable for advanced modulation formats, using non-degenerate FWM in SOAs and parallelly polarized pumps. We demonstrate the wavelength conversion of polarization-multiplexed (PM)-QPSK, PM-16QAM and a Nyquist WDM super-channel modulated with PM-QPSK signals at a baud rate of 12.

Terahertz-bandwidth coherence measurements of a quantum dash laser in passive and active mode-locking operation.

This research carries out coherence measurements of a 42.7 GHz quantum dash (QDash) semiconductor laser when passively, electrically, and optically mode-locked. Coherence of the spectral lines from the mode-locked laser is determined by examining the radio frequency beat-tone linewidth as the mode spacing is increased up to 1.