Aneesh Sobhanan

Name of Guide :Dr. Deepa Venkitesh
Year of Joining: 2015
Research Topic: Optical signal processing using Semiconductor Optical Amplifier
Position: PhD


  • Pursued B.Tech in Electronics and Communication at College of Engineering Attingal (CUSAT) in 2009.
  • Pursued M.Tech in Electrical Engineering (specialization in photonics EE5) from IIT Madras in 2014.

Current Research:

Optical phase conjugation (OPC) is recognized as one of the efficient methods to mitigate the impairments due to both chromatic dispersion and Kerr nonlinearities in long haul optical fiber transmission systems. Optical phase conjugation is also a critical functionality in achieving phase sensitive amplification (PSA) where a noise figure of smaller than 3 dB is achievable. The second and third order nonlinearities in different nonlinear media such as PPLN, HNLF and dielectric wave-guides have been used in the past to successfully demonstrate optical phase conjugation. However, the power required to initiate nonlinearities is of the order of tens/hundreds of mW for efficient nonlinear conversion which renders them impractical. Semiconductor optical amplifiers (SOA) on the other hand have proved to be an efficient and compact platform that requires much smaller optical power levels to invoke nonlinearities. In the past, we have demonstrated phase conjugation, wavelength conversion and phase quantization using nonlinear semiconductor optical amplifier (NL-SOA). The use of SOAs as wide-band amplifiers are also becoming popular in the recent past. The inherent phase distortion from SOAs with single channel and few WDM channels have to be reduced, which is also an interesting research problem. My research focuses on using SOAs for all these different applications and check its feasibility in the optical communication systems.


1. Aneesh. S, K. Saikrishna Reddy and D. Venkitesh, “Polarization division multiplexed-duobinary modulation format for long-reach passive optical network” Opt Quant Electron 48, 284 (2016)

2. Aneesh Sobhanan, and Deepa Venkitesh.“Polarization Insensitive Phase conjugation Using Single Pump Bragg-scattering Four-wave Mixing in Semiconductor Optical Ampli er Opt. Express 26, 22761-22772 (2018)

3. A. Sobhanan, L. N. Venkatasubramani, R. D. Koilpillai and D. Venkitesh, “Polarization-Insensitive Phase Conjugation of QPSK Signal Using Bragg-Scattering FWM in SOA,” in IEEE Photonics Technology Letters, vol. 31, no. 12, pp. 919-922, 15 June15, 2019.

4. A. Sobhanan, L. N. Venkatasubramani, R. D. Koilpillai and D. Venkitesh,”Dispersion and nonlinearity distortion compensation of the QPSK/16QAM signals using Optical phase conjugation in nonlinear SOAs“, accepted in IEEE Photonics Journal (2020).


5. A. Sobhanan and D. Venkitesh, “In uence of Polarization Transformation in Phase Conjugation of Polari- zation Multiplexed Data using Bragg-Scattering FWM in nonlinear SOAs”. arXiv preprint arXiv:1903.11044. 2019 Mar 26.


1. A. Sobhanan, M. Pelusi, T. Inoue, D. Venkitesh and S. Namiki “Compensation of SOA Nonlinear Distortions by Mid-stage Optical Phase Conjugation,” accepted for Oral Presentation in OFC 2020

2. A. Sobhanan, L. Narayanan, R. D. Koilpillai, and D. Venkitesh, “In uence of Polarization Transformation in Phase Conjugation of PM-QPSK in Nonlinear SOAs,” paper JTh2A.83, CLEO 2019.

3. A. Sobhanan, V. A. M. Karthik, L. V. Narayanan, R. D. Koilpillai, and D. Venkitesh, “Experimental Analysis of Noise Transfer in Optical Phase Conjugation Process in Nonlinear SOA,” paper W2A.38, OFC 2019.

4. Aneesh Sobhanan, Aravind P. Anthur, Liam P. Barry and Deepa Venkitesh. “Four-level phase quantization using optimized GER in Semiconductor Optical Ampli ers,” in the International Conference on Fiber Optics and Photonics-2018

5. L. Narayanan, A. Sobhanan, D. Venkitesh, and R. D. Koilpillai, “400 Gbps PM-QPSK Transmission for Metro-DCI Applications Employing 20 Gbaud Transmitter,” paper JW4A.81, FiO 2018.

6. A. Sobhanan, L. Narayanan, D. Koilpillai, and D. Venkitesh, “Polarization Insensitive Phase Conjugation Using Single-pump Four Wave Mixing in SOA,” paper Tu3D.4, CLEO-PR 2018.

7. A. Sobhanan, A. N. Iyer, A. P. Anthur, L. P. Barry, and D. Venkitesh, “Pump correlation requirements for four wave mixing-based phase quantization schemes,” paper Tu3D.3, CLEO-PR 2018.

8. Arjun Iyer, Aneesh Sobhanan, Deepa Venkitesh, “Optimization of Four-Wave Mixing Based Multilevel Phase Quantization through Gain Extinction Ratio”, PP42, IEEE WRAP-2017.

9. S. K. Dacha, A. N. Iyer, A. Sobhanan and D. Venkitesh, “Regeneration of 10 Gbps BPSK signals through phase sensitive ampli cation coupled with injection locking,” pp. 1-6. NCC 2017.

10. A. Sobhanan, A. Anthur, L. Barry, D. Venkitesh, “Power optimization of FWM-based phase sensitive ampli cation in SOA,” SpW3F.2, Advanced Photonics-2017.

11. Aneesh. S and D. Venkitesh, “Modi ed phase matching conditions for optical phase conjugation in highly nonlinear bers”, Tu4A.15, 13th International Conference on Fiber Optics and Photonics-2016.

12. Aneesh. S, Krithika. V R, and D. Venkitesh, “Counter-propagating cross-polarized pumps for efficient conjugate generation using FWM in SOA” paper JT4A.16, ACOFT 2016.

13.K. Saikrishna Reddy, S. Aneesh, and D. Venkitesh, “Duobinary Modulation Format for Increased split ratio in long-reach Passive Optical Networks,” paper T3A.55, in 12th International Conference on Fiber Optics and Photonics 2014.

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