Abstract

The microring-assisted (MRA) Mach-Zehnder (MZ) modulator offers a potential solution to attaining highly linear optical modulators. In this paper, the influence of waveguide loss on the linearity property of the MRA-MZ modulator is analyzed. The way to choose the biasing points is introduced. Analysis shows that the linearity of the MRA-MZ modulator is high, even at low-loss conditions. By properly setting the biasing phases, the 2nd - and 3rd-order harmonic terms of the modulation curve can be removed. The linearity range can reach 90% when the round-trip loss of the microring is less than 3 dB. The maximum modulation depth is the main factor that limits the linearity range of the modulation curve when the loss is large, but with proper power ratio setting between the two arms of the MZ interferometer, the intrinsic maximum modulation depth can be improved and the linearity range can be kept large.

© 2004 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |

  1. R. Alferness, "Waveguide electrooptic modulators," IEEE T. Microwave Theory and Techniques 82, 1121�??1137 (1982)
    [CrossRef]
  2. J. Yang, Q. Zhou, Z. Wu, T. Wu, M. Wang, Y. Takahasi, K. Tada, "GaAs/GaAlAs travelling-wave directional coupler modulators: I. Design & II experiment," Acta Optica Sinica, 17, 581-585 & 782-785 (1997).
  3. Y. Shi, C. Zhang, H. Zhang, J. Bechtel, L. Dalton, B. Robinson, and W. Steier, �??Low (Sub-1-Volt) halfwave voltage polymeric electro-optic modulators achieved by controlling chromophore shape,�?? Science 288, 119-122 (2000).
    [CrossRef]
  4. J. Yang, Q. Zhou, X. Jiang, M. Wang, and R. Chen, �??Polymer-based electro-optical circular-polarization modulator,�?? IEEE Photon. Technol. Lett. 16, 96-98 (2004).
    [CrossRef]
  5. E. Zolotov, R. Tavlykaev, �??Integrated optical Mach-Zehnder modulator with a Linearized modulation characteristic,�?? Sov. J. Quantum Electron. 18, 401-402 (1988).
    [CrossRef]
  6. S. Korotky, R. Ridder, �??Dual parallel modulation scheme for low-distortion analog optical transmission,�?? IEEE J. Select. Areas Commun. 8, 1377�??1381 (1990).
    [CrossRef]
  7. M. Farwell, Z. Lin, E. Wooten, and W. Chang, �??An electrooptic intensity modulator with improved linearity,�?? IEEE Photon. Technol. Lett. 3, 792-795 (1991).
    [CrossRef]
  8. A. Djupsjobacka, "A linearization concept for integrated-optic modulators," IEEE Photon. Technol. Lett. 4, 869-872 (1992).
    [CrossRef]
  9. R. Tavlykaev, R. Ramaswamy, �??Highly linear Y-fed directional coupler modulator with low intermodulation distortion,�?? J. Lightwave Technol. 17 282�??291 (1999).
    [CrossRef]
  10. Q. Zhou, J. Yang, Z. Shi, Y. Jiang, B. Howley, and R. Chen, "Performance limitations of a Y-branch directional-coupler-based polymeric high-speed electro-optical modulator," Opt. Eng. 43, 806-811 (2004).
    [CrossRef]
  11. B. Little, J. Foresi, G. Steinmeyer, E. Thoen, S. Chu, H. Haus, E. Ippen, L. Kimerling, W. Greene, �??Ultra-compact Si-SiO2 microring resonator optical channel dropping filters,�?? IEEE Photon. Technol. Lett. 10, 549 �??551 (1998).
    [CrossRef]
  12. J. Yang, Q. Zhou, F. Zhao, X. Jiang, B. Howley, M. Wang, R. Chen, �??Characteristics of optical bandpass filters employing series-cascaded double-ring resonators,�?? Opt. Commun. 228 91-98 (2003).
    [CrossRef]
  13. Y. Hatakeyama, T. Hanai, S. Suzuki, Y. Kokubun, "Loss-less multilevel crossing of busline waveguide in vertically coupled microring resonator filter," IEEE Photon. Technol. Lett. 16, 473- 475 (2004).
    [CrossRef]
  14. C. Madsen, J. Zhao, Optical Filter Design and Analysis: A Signal Processing Approach, (John Wiley & Sons, Inc., New York, 1999).
  15. X. Xie, J. Khurgin, J. Kang, F. Chow, "Linearized Mach-Zehnder intensity modulator," IEEE Photon. Technol. Lett. 15, 531�??533 (2003).
    [CrossRef]
  16. G. Betts, L. Walpita, W. Chang, R. Mathis, �??On the linear dynamic range of integrated electrooptical modulators,�?? IEEE J. Quantum Electron. 22, 1009-1011 (1986).
    [CrossRef]

Acta Optica Sinica (1)

J. Yang, Q. Zhou, Z. Wu, T. Wu, M. Wang, Y. Takahasi, K. Tada, "GaAs/GaAlAs travelling-wave directional coupler modulators: I. Design & II experiment," Acta Optica Sinica, 17, 581-585 & 782-785 (1997).

IEEE J. Quantum Electron. (1)

G. Betts, L. Walpita, W. Chang, R. Mathis, �??On the linear dynamic range of integrated electrooptical modulators,�?? IEEE J. Quantum Electron. 22, 1009-1011 (1986).
[CrossRef]

IEEE J. Select. Areas Commun. (1)

S. Korotky, R. Ridder, �??Dual parallel modulation scheme for low-distortion analog optical transmission,�?? IEEE J. Select. Areas Commun. 8, 1377�??1381 (1990).
[CrossRef]

IEEE Photon. Technol. Lett. (6)

M. Farwell, Z. Lin, E. Wooten, and W. Chang, �??An electrooptic intensity modulator with improved linearity,�?? IEEE Photon. Technol. Lett. 3, 792-795 (1991).
[CrossRef]

A. Djupsjobacka, "A linearization concept for integrated-optic modulators," IEEE Photon. Technol. Lett. 4, 869-872 (1992).
[CrossRef]

J. Yang, Q. Zhou, X. Jiang, M. Wang, and R. Chen, �??Polymer-based electro-optical circular-polarization modulator,�?? IEEE Photon. Technol. Lett. 16, 96-98 (2004).
[CrossRef]

X. Xie, J. Khurgin, J. Kang, F. Chow, "Linearized Mach-Zehnder intensity modulator," IEEE Photon. Technol. Lett. 15, 531�??533 (2003).
[CrossRef]

B. Little, J. Foresi, G. Steinmeyer, E. Thoen, S. Chu, H. Haus, E. Ippen, L. Kimerling, W. Greene, �??Ultra-compact Si-SiO2 microring resonator optical channel dropping filters,�?? IEEE Photon. Technol. Lett. 10, 549 �??551 (1998).
[CrossRef]

Y. Hatakeyama, T. Hanai, S. Suzuki, Y. Kokubun, "Loss-less multilevel crossing of busline waveguide in vertically coupled microring resonator filter," IEEE Photon. Technol. Lett. 16, 473- 475 (2004).
[CrossRef]

IEEE T. Microwave Theory and Techniques (1)

R. Alferness, "Waveguide electrooptic modulators," IEEE T. Microwave Theory and Techniques 82, 1121�??1137 (1982)
[CrossRef]

J. Lightwave Technol. (1)

Opt. Commun. (1)

J. Yang, Q. Zhou, F. Zhao, X. Jiang, B. Howley, M. Wang, R. Chen, �??Characteristics of optical bandpass filters employing series-cascaded double-ring resonators,�?? Opt. Commun. 228 91-98 (2003).
[CrossRef]

Opt. Eng. (1)

Q. Zhou, J. Yang, Z. Shi, Y. Jiang, B. Howley, and R. Chen, "Performance limitations of a Y-branch directional-coupler-based polymeric high-speed electro-optical modulator," Opt. Eng. 43, 806-811 (2004).
[CrossRef]

Science (1)

Y. Shi, C. Zhang, H. Zhang, J. Bechtel, L. Dalton, B. Robinson, and W. Steier, �??Low (Sub-1-Volt) halfwave voltage polymeric electro-optic modulators achieved by controlling chromophore shape,�?? Science 288, 119-122 (2000).
[CrossRef]

Sov. J. Quantum Electron. (1)

E. Zolotov, R. Tavlykaev, �??Integrated optical Mach-Zehnder modulator with a Linearized modulation characteristic,�?? Sov. J. Quantum Electron. 18, 401-402 (1988).
[CrossRef]

Other (1)

C. Madsen, J. Zhao, Optical Filter Design and Analysis: A Signal Processing Approach, (John Wiley & Sons, Inc., New York, 1999).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (8)

Fig. 1.
Fig. 1.

Schematic diagram of the linearity-enhanced MZ modulator with a microring resonator coupled to one of its arms. The modulation signal is applied to the microring.

Fig. 2.
Fig. 2.

General case of modulation curve (solid) and relocation of the biasing phase θ 0.

Fig. 3.
Fig. 3.

Phase bias applied on the arms, at which the 2nd -order harmonic term of the modulation curve vanishes. The corresponding 3rd-order term is shown in (b).

Fig. 4.
Fig. 4.

(a) Transmission coefficient, with which both the 2nd- and 3rd-order harmonic terms of the modulation curve vanish, and (b) the corresponding phase bias applied on the arms of the MZ interferometer. The 1st- and 5th-order terms are in (c).

Fig. 5.
Fig. 5.

(a) Linearity range m of the MRA-MZ modulator at the loss-free case. (b) Modulation curve of the MRA-MZ modulator with the transmission coefficient of 0.35 and the deviation.

Fig. 6.
Fig. 6.

Linearity range versus transmission coefficient under different attenuation factors.

Fig. 7.
Fig. 7.

(a) Maximum linearity range m and m’ of the MRA-MZ modulator with various attenuation factors, and (b) the corresponding transmission coefficient. The corresponding phase bias applied on the arms of the MZ interferometer is in (c).

Fig. 8.
Fig. 8.

Modulation curve of the MRA-MZ modulator with (a) the imbalance ratio ζ = 1.4 and (b) the balance ratio ζ =1.0.

Equations (9)

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

I out = I 0 4 [ σ 01 2 a r 2 ( θ ) + σ 02 2 + 2 σ 01 σ 02 a r ( θ ) cos ( φ 1 + φ r ( θ ) φ 2 ) ]
a r 2 ( θ ) = ρ 2 + σ 2 2 σρ cos θ 1 + σ 2 ρ 2 2 σρ cos θ
φ r ( θ ) = arctan [ ( 1 + ρ 2 ) σ sin θ ( 1 + σ 2 ) ρ σ cos θ ( 1 + ρ 2 ) ]
I out = I 0 σ 01 2 4 [ 1 + a r 2 ( θ ) + 2 a r ( θ ) cos ( Δ φ + φ r ( θ ) ) ]
I out ( Δ θ ) = I 0 σ 01 2 n 1 n I ( n ) ( 0 ) ( Δ θ ) n
θ 0 = θ Max + θ Min 2
m = I out U I out L I out Max
I out ( Δ θ ) f ( Δ θ ) η Δ I out Max , where Δ θ L Δ θ Δ θ U
I out = I 0 σ 01 2 2 ( 1 + ζ 2 ) [ 1 + ζ 2 a r 2 ( θ ) + 2 ζ a r ( θ ) cos ( Δ φ + φ r ( θ ) ) ]

Metrics