Abstract

We show how Up-converted Coherent Population Oscillations (UpCPO) enable to get rid of the intrinsic limitation of the carrier lifetime, leading to the generation of time delays at any high frequencies in a single SOA device. The linear dependence of the RF phase shift with respect to the RF frequency is theoretically predicted and experimentally evidenced at 16 and 35 GHz.

© 2011 OSA

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References

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  1. R. W. Boyd and D. J. Gauthier, “Controlling the velocity of light pulses,” Science 326, 1074–1077 (2009).
    [CrossRef] [PubMed]
  2. P.-C. Ku, F. Sedgwick, C. J. Chang-Hasnain, P. Palinginis, T. Li, H. Wang, S.-W. Chang, and S.-L. Chuang, “Slow light in semiconductor quantum wells,” Opt. Lett. 29, 2291–2293 (2004).
    [CrossRef] [PubMed]
  3. J. B. Khurgin, “Optical buffers based on slow light in electromagnetically induced transparent media and coupled resonator structures: comparative analysis,” J. Opt. Soc. Am. B 22, 1062–1074 (2005).
    [CrossRef]
  4. K. Y. Song, M. Herráez, and L. Thévenaz, “Observation of pulse delaying and advancement in optical fibers using stimulated brillouin scattering,” Opt. Express 13, 82–88 (2005).
    [CrossRef] [PubMed]
  5. J. Sharping, Y. Okawachi, and A. Gaeta, “Wide bandwidth slow light using a raman fiber amplifier,” Opt. Express 13, 6092–6098 (2005).
    [CrossRef] [PubMed]
  6. J. Mørk, R. Kjær, M. van der Poel, and K. Yvind, “Slow light in a semiconductor waveguide at gigahertz frequencies,” Opt. Express 13, 8136–8145 (2005).
    [CrossRef] [PubMed]
  7. S. Sales Maicas, F. Ohman, J. Capmany, and J. Mørk, “Controlling microwave signals by means of slow and fast light effects in soa-ea structures,” IEEE Photon. Technol. Lett. 19, 1589–1591 (2007).
    [CrossRef]
  8. E. Shumakher, S. O’Dúill, and G. Eisenstein, “Signal-to-noise ratio of a semiconductor optical-amplifier-based optical phase shifter,” Opt. Lett. 34, 1940–1942 (2009).
    [CrossRef] [PubMed]
  9. L. Brillouin and A. Sommerfeld, Wave Propagation and Group Velocity (New York, Academic Press, 1960).
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    [CrossRef]
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    [CrossRef] [PubMed]
  13. J. Capmany, B. Ortega, and D. Pastor, “A tutorial on microwave photonic filters,” J. Lightwave Technol. 24, 201 (2006).
    [CrossRef]
  14. P. Morton and J. Khurgin, “Microwave photonic delay line with separate tuning of the optical carrier,” IEEE Photon. Technol. Lett. 21, 1686–1688 (2009).
    [CrossRef]
  15. S. Chin, L. Thévenaz, J. Sancho, S. Sales, J. Capmany, P. Berger, J. Bourderionnet, and D. Dolfi, “Broadband true time delay for microwave signal processing, using slow light based on stimulated brillouin scattering in optical fibers,” Opt. Express 18, 22599–22613 (2010).
    [CrossRef] [PubMed]
  16. M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Observation of ultraslow light propagation in a ruby crystal at room temperature,” Phys. Rev. Lett. 90, 113903 (2003).
    [CrossRef] [PubMed]
  17. M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Superluminal and slow light propagation in a room-temperature solid,” Science 301, 200–202 (2003).
    [CrossRef] [PubMed]
  18. P. Berger, J. Bourderionnet, M. Alouini, F. Bretenaker, and D. Dolfi, “Theoretical study of the spurious-free dynamic range of a tunable delay line based on slow light in soa,” Opt. Express 17, 20584–20597 (2009).
    [CrossRef] [PubMed]
  19. S. O’Dúill, E. Shumakher, and G. Eisenstein, “Noise properties of microwave phase shifters based on semiconductor optical amplifiers,” J. Lightwave Technol. 28, 791 –797 (2010).
    [CrossRef]
  20. P. Berger, J. Bourderionnet, F. Bretenaker, D. Dolfi, S. O’Dúill, G. Eisenstein, and M. Alouini, “Intermodulation distortion in microwave phase shifters based on slow and fast light propagation in semiconductor optical amplifiers,” Opt. Lett. 35, 2762–2764 (2010).
    [CrossRef] [PubMed]
  21. J. Lloret, F. Ramos, J. Sancho, I. Gasulla, S. Sales, and J. Capmany, “Noise spectrum characterization of slow light soa-based microwave photonic phase shifters,” IEEE Photon. Technol. Lett. 22, 1005 –1007 (2010).
    [CrossRef]
  22. J. Lloret, F. Ramos, W. Xue, J. Sancho, I. Gasulla, S. Sales, J. Moerk, and J. Capmany, “The influence of optical filtering on the noise performance of microwave photonic phase shifters based on soas,” J. Lightwave Technol. 29, 1746–1752 (2011).
    [CrossRef]
  23. W. Xue, Y. Chen, F. Öhman, S. Sales, and J. Mørk, “Enhancing light slow-down in semiconductor optical amplifiers by optical filtering,” Opt. Lett. 33, 1084–1086 (2008).
    [CrossRef] [PubMed]
  24. P. Berger, J. Bourderionnet, G. de Valicourt, R. Brenot, D. Dolfi, F. Bretenaker, and M. Alouini, “Experimental demonstration of enhanced slow and fast light by forced coherent population oscillations in a semiconductor optical amplifier,” Opt. Lett. 35, 2457 (2010).
    [CrossRef] [PubMed]
  25. Y.-K. Seo, C.-S. Choi, and W.-Y. Choi, “All-optical signal up-conversion for radio-on-fiber applications using cross-gain modulation in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 14, 1448 – 1450 (2002).
    [CrossRef]
  26. Y.-K. Seo, J.-H. Seo, and W.-Y. Choi, “Photonic frequency-upconversion efficiencies in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 15, 751 –753 (2003).
    [CrossRef]
  27. M. Pu, L. Liu, W. Xue, Y. Ding, H. Ou, K. Yvind, and J. M. Hvam, “Widely tunable microwave phase shifter based on silicon-on-insulator dual-microring resonator,” Opt. Express 18, 6172–6182 (2010).
    [CrossRef] [PubMed]

2011

2010

P. Berger, M. Alouini, J. Bourderionnet, F. Bretenaker, and D. Dolfi, “Dynamic saturation in semiconductor optical amplifiers: accurate model, role of carrier density, and slow light,” Opt. Express 18, 685–693 (2010).
[CrossRef] [PubMed]

M. Pu, L. Liu, W. Xue, Y. Ding, H. Ou, K. Yvind, and J. M. Hvam, “Widely tunable microwave phase shifter based on silicon-on-insulator dual-microring resonator,” Opt. Express 18, 6172–6182 (2010).
[CrossRef] [PubMed]

S. O’Dúill, E. Shumakher, and G. Eisenstein, “Noise properties of microwave phase shifters based on semiconductor optical amplifiers,” J. Lightwave Technol. 28, 791 –797 (2010).
[CrossRef]

P. Berger, J. Bourderionnet, G. de Valicourt, R. Brenot, D. Dolfi, F. Bretenaker, and M. Alouini, “Experimental demonstration of enhanced slow and fast light by forced coherent population oscillations in a semiconductor optical amplifier,” Opt. Lett. 35, 2457 (2010).
[CrossRef] [PubMed]

P. Berger, J. Bourderionnet, F. Bretenaker, D. Dolfi, S. O’Dúill, G. Eisenstein, and M. Alouini, “Intermodulation distortion in microwave phase shifters based on slow and fast light propagation in semiconductor optical amplifiers,” Opt. Lett. 35, 2762–2764 (2010).
[CrossRef] [PubMed]

S. Chin, L. Thévenaz, J. Sancho, S. Sales, J. Capmany, P. Berger, J. Bourderionnet, and D. Dolfi, “Broadband true time delay for microwave signal processing, using slow light based on stimulated brillouin scattering in optical fibers,” Opt. Express 18, 22599–22613 (2010).
[CrossRef] [PubMed]

J. Lloret, F. Ramos, J. Sancho, I. Gasulla, S. Sales, and J. Capmany, “Noise spectrum characterization of slow light soa-based microwave photonic phase shifters,” IEEE Photon. Technol. Lett. 22, 1005 –1007 (2010).
[CrossRef]

2009

2008

2007

S. Sales Maicas, F. Ohman, J. Capmany, and J. Mørk, “Controlling microwave signals by means of slow and fast light effects in soa-ea structures,” IEEE Photon. Technol. Lett. 19, 1589–1591 (2007).
[CrossRef]

2006

2005

2004

2003

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Observation of ultraslow light propagation in a ruby crystal at room temperature,” Phys. Rev. Lett. 90, 113903 (2003).
[CrossRef] [PubMed]

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Superluminal and slow light propagation in a room-temperature solid,” Science 301, 200–202 (2003).
[CrossRef] [PubMed]

Y.-K. Seo, J.-H. Seo, and W.-Y. Choi, “Photonic frequency-upconversion efficiencies in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 15, 751 –753 (2003).
[CrossRef]

2002

Y.-K. Seo, C.-S. Choi, and W.-Y. Choi, “All-optical signal up-conversion for radio-on-fiber applications using cross-gain modulation in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 14, 1448 – 1450 (2002).
[CrossRef]

1996

Alouini, M.

Antoine, J.

Berger, P.

Bigelow, M. S.

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Observation of ultraslow light propagation in a ruby crystal at room temperature,” Phys. Rev. Lett. 90, 113903 (2003).
[CrossRef] [PubMed]

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Superluminal and slow light propagation in a room-temperature solid,” Science 301, 200–202 (2003).
[CrossRef] [PubMed]

Bourderionnet, J.

Boyd, R. W.

R. W. Boyd and D. J. Gauthier, “Controlling the velocity of light pulses,” Science 326, 1074–1077 (2009).
[CrossRef] [PubMed]

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Observation of ultraslow light propagation in a ruby crystal at room temperature,” Phys. Rev. Lett. 90, 113903 (2003).
[CrossRef] [PubMed]

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Superluminal and slow light propagation in a room-temperature solid,” Science 301, 200–202 (2003).
[CrossRef] [PubMed]

Brenot, R.

Bretenaker, F.

Brillouin, L.

L. Brillouin and A. Sommerfeld, Wave Propagation and Group Velocity (New York, Academic Press, 1960).

Capmany, J.

Chang, S.-W.

Chang-Hasnain, C. J.

Chen, Y.

Chin, S.

Choi, C.-S.

Y.-K. Seo, C.-S. Choi, and W.-Y. Choi, “All-optical signal up-conversion for radio-on-fiber applications using cross-gain modulation in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 14, 1448 – 1450 (2002).
[CrossRef]

Choi, W.-Y.

Y.-K. Seo, J.-H. Seo, and W.-Y. Choi, “Photonic frequency-upconversion efficiencies in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 15, 751 –753 (2003).
[CrossRef]

Y.-K. Seo, C.-S. Choi, and W.-Y. Choi, “All-optical signal up-conversion for radio-on-fiber applications using cross-gain modulation in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 14, 1448 – 1450 (2002).
[CrossRef]

Chuang, S.-L.

de Valicourt, G.

Ding, Y.

Dolfi, D.

P. Berger, J. Bourderionnet, F. Bretenaker, D. Dolfi, S. O’Dúill, G. Eisenstein, and M. Alouini, “Intermodulation distortion in microwave phase shifters based on slow and fast light propagation in semiconductor optical amplifiers,” Opt. Lett. 35, 2762–2764 (2010).
[CrossRef] [PubMed]

S. Chin, L. Thévenaz, J. Sancho, S. Sales, J. Capmany, P. Berger, J. Bourderionnet, and D. Dolfi, “Broadband true time delay for microwave signal processing, using slow light based on stimulated brillouin scattering in optical fibers,” Opt. Express 18, 22599–22613 (2010).
[CrossRef] [PubMed]

P. Berger, M. Alouini, J. Bourderionnet, F. Bretenaker, and D. Dolfi, “Dynamic saturation in semiconductor optical amplifiers: accurate model, role of carrier density, and slow light,” Opt. Express 18, 685–693 (2010).
[CrossRef] [PubMed]

P. Berger, J. Bourderionnet, G. de Valicourt, R. Brenot, D. Dolfi, F. Bretenaker, and M. Alouini, “Experimental demonstration of enhanced slow and fast light by forced coherent population oscillations in a semiconductor optical amplifier,” Opt. Lett. 35, 2457 (2010).
[CrossRef] [PubMed]

P. Berger, J. Bourderionnet, M. Alouini, F. Bretenaker, and D. Dolfi, “Theoretical study of the spurious-free dynamic range of a tunable delay line based on slow light in soa,” Opt. Express 17, 20584–20597 (2009).
[CrossRef] [PubMed]

D. Dolfi, P. Joffre, J. Antoine, J.-P. Huignard, D. Philippet, and P. Granger, “Experimental demonstration of a phased-array antenna optically controlled with phase and time delays,” Appl. Opt. 35, 5293–5300 (1996).
[CrossRef] [PubMed]

Eisenstein, G.

Gaeta, A.

Gasulla, I.

J. Lloret, F. Ramos, W. Xue, J. Sancho, I. Gasulla, S. Sales, J. Moerk, and J. Capmany, “The influence of optical filtering on the noise performance of microwave photonic phase shifters based on soas,” J. Lightwave Technol. 29, 1746–1752 (2011).
[CrossRef]

J. Lloret, F. Ramos, J. Sancho, I. Gasulla, S. Sales, and J. Capmany, “Noise spectrum characterization of slow light soa-based microwave photonic phase shifters,” IEEE Photon. Technol. Lett. 22, 1005 –1007 (2010).
[CrossRef]

Gauthier, D. J.

R. W. Boyd and D. J. Gauthier, “Controlling the velocity of light pulses,” Science 326, 1074–1077 (2009).
[CrossRef] [PubMed]

Granger, P.

Herráez, M.

Huignard, J.-P.

Hvam, J. M.

Joffre, P.

Khurgin, J.

P. Morton and J. Khurgin, “Microwave photonic delay line with separate tuning of the optical carrier,” IEEE Photon. Technol. Lett. 21, 1686–1688 (2009).
[CrossRef]

Khurgin, J. B.

Kjær, R.

Ku, P.-C.

Lepeshkin, N. N.

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Superluminal and slow light propagation in a room-temperature solid,” Science 301, 200–202 (2003).
[CrossRef] [PubMed]

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Observation of ultraslow light propagation in a ruby crystal at room temperature,” Phys. Rev. Lett. 90, 113903 (2003).
[CrossRef] [PubMed]

Li, T.

Liu, L.

Lloret, J.

J. Lloret, F. Ramos, W. Xue, J. Sancho, I. Gasulla, S. Sales, J. Moerk, and J. Capmany, “The influence of optical filtering on the noise performance of microwave photonic phase shifters based on soas,” J. Lightwave Technol. 29, 1746–1752 (2011).
[CrossRef]

J. Lloret, F. Ramos, J. Sancho, I. Gasulla, S. Sales, and J. Capmany, “Noise spectrum characterization of slow light soa-based microwave photonic phase shifters,” IEEE Photon. Technol. Lett. 22, 1005 –1007 (2010).
[CrossRef]

Moerk, J.

Mørk, J.

Morton, P.

P. Morton and J. Khurgin, “Microwave photonic delay line with separate tuning of the optical carrier,” IEEE Photon. Technol. Lett. 21, 1686–1688 (2009).
[CrossRef]

O’Dúill, S.

Ohman, F.

S. Sales Maicas, F. Ohman, J. Capmany, and J. Mørk, “Controlling microwave signals by means of slow and fast light effects in soa-ea structures,” IEEE Photon. Technol. Lett. 19, 1589–1591 (2007).
[CrossRef]

Öhman, F.

Okawachi, Y.

Ortega, B.

Ou, H.

Palinginis, P.

Pastor, D.

Philippet, D.

Pu, M.

Ramos, F.

J. Lloret, F. Ramos, W. Xue, J. Sancho, I. Gasulla, S. Sales, J. Moerk, and J. Capmany, “The influence of optical filtering on the noise performance of microwave photonic phase shifters based on soas,” J. Lightwave Technol. 29, 1746–1752 (2011).
[CrossRef]

J. Lloret, F. Ramos, J. Sancho, I. Gasulla, S. Sales, and J. Capmany, “Noise spectrum characterization of slow light soa-based microwave photonic phase shifters,” IEEE Photon. Technol. Lett. 22, 1005 –1007 (2010).
[CrossRef]

Sales, S.

Sales Maicas, S.

S. Sales Maicas, F. Ohman, J. Capmany, and J. Mørk, “Controlling microwave signals by means of slow and fast light effects in soa-ea structures,” IEEE Photon. Technol. Lett. 19, 1589–1591 (2007).
[CrossRef]

Sancho, J.

Sedgwick, F.

Seo, J.-H.

Y.-K. Seo, J.-H. Seo, and W.-Y. Choi, “Photonic frequency-upconversion efficiencies in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 15, 751 –753 (2003).
[CrossRef]

Seo, Y.-K.

Y.-K. Seo, J.-H. Seo, and W.-Y. Choi, “Photonic frequency-upconversion efficiencies in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 15, 751 –753 (2003).
[CrossRef]

Y.-K. Seo, C.-S. Choi, and W.-Y. Choi, “All-optical signal up-conversion for radio-on-fiber applications using cross-gain modulation in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 14, 1448 – 1450 (2002).
[CrossRef]

Sharping, J.

Shumakher, E.

Sommerfeld, A.

L. Brillouin and A. Sommerfeld, Wave Propagation and Group Velocity (New York, Academic Press, 1960).

Song, K. Y.

Thévenaz, L.

van der Poel, M.

Wang, H.

Xue, W.

Yao, J.

Yvind, K.

Appl. Opt.

IEEE Photon. Technol. Lett.

J. Lloret, F. Ramos, J. Sancho, I. Gasulla, S. Sales, and J. Capmany, “Noise spectrum characterization of slow light soa-based microwave photonic phase shifters,” IEEE Photon. Technol. Lett. 22, 1005 –1007 (2010).
[CrossRef]

Y.-K. Seo, C.-S. Choi, and W.-Y. Choi, “All-optical signal up-conversion for radio-on-fiber applications using cross-gain modulation in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 14, 1448 – 1450 (2002).
[CrossRef]

Y.-K. Seo, J.-H. Seo, and W.-Y. Choi, “Photonic frequency-upconversion efficiencies in semiconductor optical amplifiers,” IEEE Photon. Technol. Lett. 15, 751 –753 (2003).
[CrossRef]

S. Sales Maicas, F. Ohman, J. Capmany, and J. Mørk, “Controlling microwave signals by means of slow and fast light effects in soa-ea structures,” IEEE Photon. Technol. Lett. 19, 1589–1591 (2007).
[CrossRef]

P. Morton and J. Khurgin, “Microwave photonic delay line with separate tuning of the optical carrier,” IEEE Photon. Technol. Lett. 21, 1686–1688 (2009).
[CrossRef]

J. Lightwave Technol.

J. Opt. Soc. Am. B

Opt. Express

J. Sharping, Y. Okawachi, and A. Gaeta, “Wide bandwidth slow light using a raman fiber amplifier,” Opt. Express 13, 6092–6098 (2005).
[CrossRef] [PubMed]

J. Mørk, R. Kjær, M. van der Poel, and K. Yvind, “Slow light in a semiconductor waveguide at gigahertz frequencies,” Opt. Express 13, 8136–8145 (2005).
[CrossRef] [PubMed]

K. Y. Song, M. Herráez, and L. Thévenaz, “Observation of pulse delaying and advancement in optical fibers using stimulated brillouin scattering,” Opt. Express 13, 82–88 (2005).
[CrossRef] [PubMed]

S. Chin, L. Thévenaz, J. Sancho, S. Sales, J. Capmany, P. Berger, J. Bourderionnet, and D. Dolfi, “Broadband true time delay for microwave signal processing, using slow light based on stimulated brillouin scattering in optical fibers,” Opt. Express 18, 22599–22613 (2010).
[CrossRef] [PubMed]

P. Berger, J. Bourderionnet, M. Alouini, F. Bretenaker, and D. Dolfi, “Theoretical study of the spurious-free dynamic range of a tunable delay line based on slow light in soa,” Opt. Express 17, 20584–20597 (2009).
[CrossRef] [PubMed]

P. Berger, M. Alouini, J. Bourderionnet, F. Bretenaker, and D. Dolfi, “Dynamic saturation in semiconductor optical amplifiers: accurate model, role of carrier density, and slow light,” Opt. Express 18, 685–693 (2010).
[CrossRef] [PubMed]

M. Pu, L. Liu, W. Xue, Y. Ding, H. Ou, K. Yvind, and J. M. Hvam, “Widely tunable microwave phase shifter based on silicon-on-insulator dual-microring resonator,” Opt. Express 18, 6172–6182 (2010).
[CrossRef] [PubMed]

Opt. Lett.

Phys. Rev. Lett.

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Observation of ultraslow light propagation in a ruby crystal at room temperature,” Phys. Rev. Lett. 90, 113903 (2003).
[CrossRef] [PubMed]

Science

M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, “Superluminal and slow light propagation in a room-temperature solid,” Science 301, 200–202 (2003).
[CrossRef] [PubMed]

R. W. Boyd and D. J. Gauthier, “Controlling the velocity of light pulses,” Science 326, 1074–1077 (2009).
[CrossRef] [PubMed]

Other

L. Brillouin and A. Sommerfeld, Wave Propagation and Group Velocity (New York, Academic Press, 1960).

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Figures (4)

Fig. 1
Fig. 1

Tunable True Time Delay (TTD) (a) can be generated by combining a microwave phase shifter (b) and a tunable delay generator (c). These devices only need to work over the instantaneous bandwidth Binst near the operating frequency fop. An easy reconfiguration of the operating frequency over a wide range (Δfop) is required for microwave applications.

Fig. 2
Fig. 2

Principle of integrated delay generator using UpCPO in a SOA. An optically carried RF signal, at a high RF frequency fop, propagates through the SOA. A second optically carried RF signal, at a low RF frequency (fcpo < a few GHz), induces CPO. The modal gain g is then modulated at fcpo. The gain modulation at fcpo generates then two optically carried RF signals at f = fopfcpo or f = fop + fcpo. The CPO effect is controlled by the average gain < g > (through the current or the input optical power), which permits to control the delay τ of the RF signal at f.

Fig. 3
Fig. 3

Demonstration of an integrated delay generator using UpCPO in SOA. A first channel is composed of a laser diode and a Mach Zehnder intensity modulator (MZM), and is dedicated to the electrical to optical conversion of the RF signal at the operating frequency fop. The second channel, composed of a directly modulated laser diode, optically converts the RF signal which is at a low RF frequency fcpo. Both channels propagate through the SOA. The RF signal at the frequency f = fopfcpo or f = fop + fcpo is retrieved in the electrical domain by a photodiode and analyzed by a Vector Network Analyzer (VNA). The VNA generates the signal at the frequency f which is converted by a RF mixer down to fcpo.

Fig. 4
Fig. 4

The figures (A.1) and (A.2) respectively represent the typical simulated and measured phase shifts induced in the SOA by usual CPO with respect to the RF frequency. By adjusting the current from 42 mA to 200 mA, the delays are tunable from 0 to 380ps, over an instantaneous bandwidth of 320MHz. The operating frequency range is limited to the instantaneous bandwidth. The figure (B.1) represents the simulated phase shift induced in a SOA with respect to frequency, by combining XGM and CPO, around an arbitrarily high frequency fop. (B.2) and (B.3) represent the corresponding measured phase shift at fop = 16GHz and fop = 35GHz, respectively. By adjusting the current from 80 mA to 599 mA, delays are tunable from 0 to 89ps, over an instantaneous bandwidth of 1.2GHz. Here we experimentally show that UpCPO enable the operating frequency to reach 35 GHz, far beyond the intrinsic bandwidth of CPO.

Equations (3)

Equations on this page are rendered with MathJax. Learn more.

g cpo = < g > M cpo / U s 1 + U / U s 2 i π f cpo τ s ,
d M signal + dz = ( Γ < g > γ ) M signal + + Γ g cpo [ 1 2 ( M op R + M op B ) + i α 2 ( M op R M op B ) ] ,
d M signal dz = ( Γ < g > γ ) M signal + Γ g cpo * [ 1 2 ( M op R + M op B ) + i α 2 ( M op R M op B ) ] ,

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