Research Areas
We utilize fiber lasers as the workhorse of our research. Owing to their unparalleled features like power scalability and robust operation, they are one of the most sought-after laser sources. Our work mainly focuses on combining laser physics and nonlinear photonics to tailor the output properties of these lasers, such as wavelength, linewidth, and power. Below are two of the research directions we are currently exploring:
Supercontinuum lasers: While lasers are generally considered monochromatic sources with small linewidths, supercontinuum lasers provide broadband output, typically covering several hundreds of nanometers, making them broadband lasers. Supercontinuum lasers offer the benefits of conventional broadband light sources (like SLEDs or halogen lamps) but with a million times more brightness. Additionally, they produce a diffraction-limited Gaussian beam, which results in extremely high spatial resolution. Our work focuses on improving supercontinuum sources in the following areas:
(i) Bandwidth enhancement (ii) Spectral stability
(iii) Spectral shaping (iv) Power scaling.
Tunable fiber lasers: The availability of laser sources is often limited by the absence of suitable gain media for specific wavelengths. Many applications, however, demand wavelength tunability, a requirement usually met by employing multiple independent laser sources, if available. Instead of relying on separate lasers for each wavelength, tunable lasers provide greater flexibility in experiment design and optimization. To address this limitation, we focus on wavelength-tunable Raman fiber lasers, which operate on the principle of stimulated Raman scattering. Our research aims to expand the wavelength tunability of Raman fiber lasers, improve their linewidth characteristics, and utilize them in frequency-doubling experiments to generate visible lasers.
Journal Publications
Inés Cáceres Pablo, Arun Surendran, Francesca Gallazzi, Zahra Eslami, and Goëry Genty ,"Relative intensity noise characterization of supercontinuum generation in graded-index and step-index multimode fibers", Optics Letters 50, 1236-1239 (2025).
Roopa Prakash, Vishal Choudhury, S. Arun, V. R. Supradeepa, "Pump Wavelength Flexible, Continuous-Wave Fiber Supercontinuum Using Two-Stage Spectral Broadening”, in IEEE Photonics Technology Letters, vol. 33, no. 1, pp. 31-34, Jan.1, 2021.
S. Arun, Vishal Choudhury, V. Balaswamy, and V. R. Supradeepa, "Octave-spanning, continuous-wave supercontinuum generation with record power using standard telecom fibers pumped with power-combined fiber lasers", Optics Letters 45, 1172-1175 (2020).
Santosh Aparanji, S. Arun, V. Balaswamy, and V. R. Supradeepa, "Visible light generation in the cladding of optical fibers carrying near-infrared continuous-wave lasers due to Cherenkov-phase matched harmonic conversion", Optics Letters 45, 993-996 (2020)
V. Balaswamy, Santosh Aparanji, S. Arun, Siddharth Ramachandran, and V. R. Supradeepa, "High-power, widely wavelength tunable, grating-free Raman fiber laser based on filtered feedback", Optics Letters 44, 279-282 (2019).
S. Arun, Vishal Choudhury, V. Balaswamy, and V. R. Supradeepa, "Stability analysis of high power, octave spanning, continuous-wave supercontinuum sources based on cascaded Raman scattering in standard telecom fibers", OSA Continuum 1, 1267-1276 (2018).
S Arun*, V Balaswamy*, G. Chayran, and V. R. Supradeepa, "Resonant pumping of high power fiber lasers with conventional laser diodes", OSA Continuum 1, 651-657 (2018).
S. Arun, V. Choudhury, R. Prakash and V. R. Supradeepa, "High Power, Tunable, Continuous-Wave Fiber Lasers in the L-Band Using Cascaded Raman Amplifiers", in IEEE Photonics Technology Letters, vol. 30, no. 15, pp. 1412-1415, 1 Aug.1, 2018.
Vishal Choudhury*, S. Arun*, Roopa Prakash, and V. R. Supradeepa, "High-power continuous-wave supercontinuum generation in highly nonlinear fibers pumped with high-order cascaded Raman fiber amplifiers", Applied Optics 57, 5978-5982 (2018).
S. Arun, Vishal Choudhury, V. Balaswamy, Roopa Prakash, and V. R. Supradeepa, "High power, high efficiency, continuous-wave supercontinuum generation using standard telecom fibers", Optics Express 26, 7979-7984 (2018).
V. Balaswamy*, S. Arun*, Santosh Aparanji, Vishal Choudhury, and V. R. Supradeepa, "High-power, fixed, and tunable wavelength, grating-free cascaded Raman fiber lasers", Optics Letters 43, 1574-1577 (2018).
Santosh Aparanji, V. Balaswamy, S. Arun, and V. R. Supradeepa, "Simultaneous Raman based power combining and wavelength conversion of high-power fiber lasers", Optics Express 26, 4954-4960 (2018).
V. Balaswamy*, S. Arun*, G. Chayran, and V. R. Supradeepa, "All passive architecture for high efficiency cascaded Raman conversion", Optics Express 26, 3046-3053 (2018).
Arun S. & Supradeepa, V.R., ” High power fiber lasers in the SWIR band using Raman lasers”, CSI Transactions on ICT, 5(2), 143–148, 2017.
Conference Proceedings
Arun Surendran, Tuuli Nissinen, Zahra Eslami, Goëry Genty, “Relative intensity noise characterization of supercontinuum generation in graded index and step index multimode fibers”, Paper 12405-12, Photonics West 2023.
A. Goswami, S. Dash, R. Deheri, S. Arun, and V. Supradeepa, "Pulsed Cascaded Raman Fiber Laser with Wide Wavelength Tunability," in Proceedings of the 2022 Conference on Lasers and Electro-Optics Pacific Rim, Technical Digest Series (Optica Publishing Group, 2022), paper CTuP1D_02.
S.Arun, V. Gehlot, A. Santosh and V R Supradeepa,” Tunable, CW visible laser sources by frequency doubling of broadly tunable Raman fiber lasers”, Paper No: 11264-79, Nonlinear Frequency Generation and Conversion: Materials and Devices XIX, Photonics West 2020.
Vishal Choudhury, Arun Surendran, V. R. Supradeepa,” Fourier pulse shaper for high-power fiber-coupled lasers and supercontinuum sources”, Paper No: 11287-7, Photonic Instrumentation Engineering VII, Photonics West 2020.
S. Arun, Vishal Choudhury, V. Balaswamy, V. R. Supradeepa,” Spectral and Temporal Stability of Cascaded Raman based High Power, Octave Spanning, Continuous-Wave, Supercontinuum Sources”, Paper No:10902, Nonlinear Frequency Generation and Conversion: Materials and Devices XVIII, Photonics West 2019.
S. Arun, V. Choudhury, V. Balaswamy, and V. R. Supradeepa, "Power Combined, Octave-spanning, CW Supercontinuum using Standard Telecom Fiber with Output Power of 70W," in Conference on Lasers and Electro-Optics, OSA Technical Digest (online) (Optical Society of America, 2018), paper SM1K.5.
V. Balaswamy, S. Aparanji, S. Arun, S. Ramachandran, and V. R. Supradeepa, "High Power, Ultra-Widely Tunable Wavelength, Cascaded Raman Fiber Laser," in Conference on Lasers and Electro-Optics, OSA Technical Digest (online) (Optical Society of America, 2018), paper SM1K.4.
S. Aparanji, V. Balaswamy, S. Arun, and V. R. Supradeepa, "Harmonic Generation In Cascaded Raman Fiber Lasers," in Conference on Lasers and Electro-Optics, OSA Technical Digest (online) (Optical Society of America, 2018), paper JTu2A.70.
S. Arun, Vishal Choudhury, V. Balaswamy, V. R. Supradeepa, "Simple modules for high efficiency conversion of standard ytterbium doped fiber lasers into octave spanning continuous-wave supercontinuum sources," Proc. SPIE 10512, Fiber Lasers XV: Technology and Systems, 105121W (26 February 2018).
Santosh Aparanji, V. Balaswamy, S. Arun, V. R. Supradeepa, "Raman based power combining and wavelength conversion of high power ytterbium fiber lasers," Proc. SPIE 10512, Fiber Lasers XV: Technology and Systems, 105121U (26 February 2018).
V. Balaswamy, Santosh Aparanji, S. Arun, V. R. Supradeepa, "High-power tunable grating-free cascaded Raman fiber lasers," Proc. SPIE 10528, Optical Components and Materials XV, 1052816 (22 February 2018).
Roopa Prakash, Vishal Choudhury, S. Arun, V. R. Supradeepa, "Low power generation of equalized broadband CW supercontinua using a novel technique incorporating modulation instability of line broadened pump," Proc. SPIE 10528, Optical Components and Materials XV, 1052817 (22 February 2018).
Santosh Aparanji, V. Balaswamy, S. Arun, V. R. Supradeepa, "Observation of a rainbow of visible colors in a near infrared cascaded Raman fiber laser and its novel application as a diagnostic tool for length resolved spectral analysis," Proc. SPIE 10516, Nonlinear Frequency Generation and Conversion: Materials and Devices XVII, 105160M (15 February 2018).
S. Arun, Vishal Choudhury, V. Balaswamy and V.R. Supradeepa,” High Power, High Efficiency, Continuous-Wave Supercontinuum Generation using Standard Telecom Fibers”, Advanced Solid State Lasers (ASSL), JM5A.31 (2017).
S. Aparanji, V. Balaswamy, S. Arun, and V. R. Supradeepa, "Simultaneous Power Combining and Wavelength Conversion of High Power Fiber Lasers," in Laser Congress 2017 (ASSL, LAC), OSA Technical Digest (online) (Optical Society of America, 2017), paper ATu3A.4.
S. Arun, V. Balaswamy, S. Aparanji, and V. R. Supradeepa, "High Power, Grating-Free, Cascaded Raman Fiber Lasers," in 2017 European Conference on Lasers and Electro-Optics and European Quantum Electronics Conference, (Optical Society of America, 2017), paper CJ_2_4.
V. Choudhury, S. Arun, R. Prakash, and V. R. Supradeepa, "High Power, Equalized, Continuous-Wave Supercontinuum Generation using Cascaded Raman Fiber Amplifiers," in 2017 European Conference on Lasers and Electro-Optics and European Quantum Electronics Conference, (Optical Society of America, 2017), paper CD_1_4.
S. Arun, V. Choudhury, R. Prakash, and V. R. Supradeepa, "High Power, Tunable, L-Band (1.6micron Wavelength Region) Fiber Lasers," in 13th International Conference on Fiber Optics and Photonics, OSA Technical Digest (online) (Optical Society of America, 2016), paper Tu3E.5.
V. Balaswamy, S. Arun, G. Chayran, and V. R. Supradeepa, "A Simplified Architecture for High Efficiency Cascaded Raman Fiber Lasers," in Conference on Lasers and Electro-Optics, OSA Technical Digest (2016) (Optical Society of America, 2016), paper SM2Q.5.
S. Arun, V. Balaswamy, G. Chayran, P. Vanitha, A. Kumar, V. R. Supradeepa, "A diode drive mechanism for always resonant pumping with laser diodes without wavelength locking," Proc. SPIE 9728, Fiber Lasers XIII: Technology, Systems, and Applications, 97281S (11 March 2016).
Patent
V. R. Supradeepa, V. Balaswamy, A. Santosh, S. Arun, ‘Device for tuning laser output’, Indian Patent, filed on 30th April, 2019.
