Kristina Bagnell

Frequency stability of a 10 GHz optical frequency comb from a semiconductor-based mode-locked laser with an intracavity 10,000 finesse etalon.

An optical frequency comb is constructed using a semiconductor gain medium with a fiber-coupled external cavity and stabilized to an intracavity 10,000 finesse etalon, which is temperature stabilized and held in a vacuum chamber at 10(-6)  Torr. Optical frequency stability measurements show that the comb has a reduced sensitivity to environmental fluctuations. An upper limit on the optical frequency variation of 100 kHz over >12  min of continuous operation is measured using a real-time spectrum analyzer. This measurement is limited by the linewidth of the reference source, and further measurements with a frequency counter show a fractional deviation of 2×10(-11) at 50 ms. Furthermore, out-of-band ASE rejection is shown to be >36  dB, a tenfold improvement over that of a laser with a 1000 finesse FPE.

Semiconductor laser based optical frequency combs — Applications in communications and signal processing

Optical frequency combs from mode-locked lasers are developed and used for realizing unique functionality for applications in ultra-wide bandwidth communication and signal processing.

Broadband, low noise modelocked semiconductor laser with intracavity programmable dispersion control

An intracavity pulseshaper is used to broaden the spectrum of a 10 GHz semiconductor frequency comb to greater than 28 nm. Timing jitter is measured to be 15.4 fs integrated from 1 kHz to 100 MHz offset.

Optical frequency combs from mode-locked diode lasers - applications in communications, signal processing & radar for avionics

Optical frequency combs from mode-locked lasers are developed and used for realizing unique functionality for applications in ultra-wide bandwidth communication and signal processing.

Tunable frequency combs for photonic applications

A high quality frequency comb with widely spaced and tunable spacing is generated via an injection locked harmonically mode-locked laser. This is achieved via adjustment of the mode-locking rate in steps of the cavity fundamental frequency. An optical SNR of 36 dB and over 7 nm of optical bandwidth is achieved. Power spectral density of the relative phase noise is shown and a marked improvement in the integrated (1Hz to 100 MHz) timing jitter from 32 fs to 12.9 fs is demonstrated, making the source ideal for frequency comb applications such as multi-heterodyne spectroscopy and novel linear modulator technology which require comb spacing flexibility.