Tunable zero-chirp pulse generator using plasma dispersion phase modulator
View Patent ↗An optical pulse generator comprising a phase modulator, wherein the phase modulator is configured to phase modulate and intensity modulate a continuous wave (CW) light signal in accordance with a received electrical signal, and an all-pass filter, the all-pass filter being coupled to the phase modulator to generate a pulsed light signal by filtering the modulated light signal from the phase modulator.
1. An optical pulse generator comprising:
a phase modulator, wherein the phase modulator is a plasma dispersion phase modulator (PDPM) configured to phase modulate a continuous wave (CW) light signal in accordance with a received electrical signal; and
an all-pass filter, the all-pass filter being coupled to the phase modulator to generate a pulsed light signal by filtering the modulated light signal from the phase modulator, wherein the all-pass filter has a tunable spectral response, and the pulsed light signal has a chirp factor that varies in accordance with a spectral location of a resonance in the spectral response of the all-pass filter.
2. The optical pulse generator of claim 1 , wherein the pulsed light signal is substantially chirp-free.
3. The optical pulse generator of claim 1 , wherein the pulsed light signal has a chirp factor ≦±0.2.
4. The optical pulse generator of claim 1 , wherein the modulated signal from the phase modulator has a chirp.
5. The optical pulse generator of claim 1 , wherein the phase modulator includes at least one of silicon, germanium, and indium phosphide material.
6. The optical pulse generator of claim 1 , wherein the all-pass filter comprises:
a coupler; and
a phase shifter,
wherein the coupler and phase shifter are arranged in a waveguide ring.
7. The optical pulse generator of claim 6 , wherein the coupler is a thermo-optic tunable coupler and the phase shifter is a thermo-optic phase shifter.
8. The optical pulse generator of claim 1 , wherein a frequency of a resonance in a spectral response of the all-pass filter and a frequency of a spectral component of the modulated light signal are different.
9. The optical pulse generator of claim 1 , wherein a peak power of the pulsed light signal is greater than a peak power of the CW light signal.
10. A data modulator system comprising the optical pulse generator of claim 1 and a chirped intensity modulator.
11. The data modulator system of claim 10 , wherein the chirped intensity modulator includes at least one of a Mach-Zehnder modulator and an electro-absorption modulator.
12. The data modulator system of claim 10 , wherein the chirped intensity modulator includes at least one of silicon, germanium, and indium phosphide material.
13. The data modulator system of claim 10 , wherein the chirped intensity modulator generates a data modulated optical signal that is effectively chirp-free.
14. The data modulator system of claim 11 , wherein the Mach-Zehnder modulator includes:
a first coupler;
a phase shifter;
a first phase modulator;
a second phase modulator; and
a second coupler,
wherein:
the first phase modulator is coupled between a first output of the first coupler and a first input of the second coupler, and
the phase shifter and the second phase modulator are coupled in series between a second output of the first coupler and a second input of the second coupler.