Dr. Chaitanya Kumar Suddapalli Profile

Dr. Chaitanya Kumar Suddapalli

Laser Scientist at ICFO - Instituto de Ciencias Fotónicas

SPIE Involvement:

Conference Program Committee | Author

Profile Summary

Chaitanya Kumar Suddapalli received Ph.D. degree in photonics with “Excellent Cum Laude with Honours” from ICFO-The Institute of Photonic Sciences, Barcelona, Spain, in 2012, for his thesis on high-power, ﬁber-laser-pumped optical parametric oscillators from the visible to mid-infrared. He is currently working as a Laser Scienctist in the reaseach and development division at Radiantis, a world leading specialist company in developing nonlinear frequency conversion sources. His research interests include ﬁber-based optical frequency conversion sources and continuous-wave and ultrafast optical parametric oscillators from the ultraviolet to mid-infrared. He has published more than 70 peer-reviewed and invited papers in leading international journals in Photonics and has presented in excess of 120 contributed, post deadline and invited papers at major international conferences such as SPIE Photonics West and CLEO-USA. Through out his career, he worked on several funded projects with active international collaborations. Some of his research works have been highlighted in Laser Focus World and Nature Photonics. He received the ICFO Ph.D. thesis award in 2013 and UPC extraordinary Ph.D. thesis award in 2014 for his outstanding contributions to applied research during his doctoral studies. Further, he was selected for the prestegious 66th Lindau Nobel Laureate meeting in 2016. He is a professional member of the Optical Society of America, The International Society for Optics and Photonics and European Physical Society. Further, he also served on several conference technical committees including MICS and Europhoton.

Publications (16)

Proceedings Article | 23 May 2018

Compact fibre-integrated femtosecond optical parametric oscillator (Conference Presentation)

Callum O'Donnell, Chaitanya Kumar Suddapalli, Therese Paoletta, Majid Ebrahim-Zadeh

Proc. SPIE. 10684, Nonlinear Optics and its Applications 2018

KEYWORDS: Optical fibers, Mirrors, Optical parametric oscillators, Femtosecond phenomena, Crystals, Silver, Optical microscopy, Laser development, Sapphire lasers, Time resolved spectroscopy

Read Abstract +

High repetition-rate coherent femtosecond sources of tunable near-IR radiation are widely used for time resolved spectroscopy and optical microscopy. We have developed a compact femtosecond optical parametric oscillator (OPO) for the near-IR in a novel configuration based on MgO doped periodically poled LiNbO3 (MgO:PPLN) synchronously pumped by a Kerr-lens-mode-locked (KLM) Ti:sapphire laser at 76 MHz. The singly-resonant OPO in a four-mirror X-cavity arrangement incorporates an 86-cm-long single mode fibre with one silver coated facet functioning as an end mirror. By coupling the resonant signal into the fibre comprising 63% of the total cavity length, the total OPO footprint is kept highly compact, while maintaining the repetition rate at 76 MHz. Moreover, the use of the optical fibre drastically alters the cavity dispersion profile compared to a free-space OPO, with the zero-dispersion wavelength shifted to ~1.3 μm. At a pump wavelength of 800 nm, the signal wavelength is tunable across 1128–1243 nm in the normal dispersion regime, and 1358–1600 nm (degeneracy) in the anomalous dispersion regime, by variation of cavity length and the crystal grating period. Tuning curves are compared to those predicted using the Sellmeier equations for MgO:PPLN and fused silica, confirming close agreement with experiment. Using a maximum pump power of ~850 mW, up to 50 mW of average signal power is extracted at 1468 nm using a 13% output coupler, and the oscillation threshold is measured to be ~600 mW. The output power is limited by an estimated coupling loss of 2.2 dB at the fibre coupler, and imperfect cavity mode-matching. Excellent passive spectral stability is observed, and a power stability of 1.1% rms is recorded. The signal beam is of high spatial quality with a TEM00 profile. Signal pulses are characterised using intensity autocorrelation, yielding pulse durations of ~130 fs at 1192 nm, very similar to those of the pump. Spectra in the anomalous dispersion regime are well-defined single peaks, while those in the normal dispersion regime exhibit a rich variety of features including symmetrical sideband formation and evidence of optical wave breakup. These features are modelled and verified using simulations based on the nonlinear Schrodinger equation. The wavelength offset of sidebands of order N is seen to follow a N0.5 dependence, analogous to those observed in the spectrum of a mode-locked soliton laser operating in the anomalous dispersion regime. To the best of our knowledge, this represents the first fibre-feedback OPO configured using a fibre facet as an end mirror; and the first time tuning in both dispersion regimes has been achieved. The combination of high intracavity dispersion and a broad phase matching bandwidth enables rapid continuous tuning across the near-IR using cavity delay, and excellent spectral stability. With suitable optics, the idler beam across 1.6–3 μm could also be extracted. This OPO represents a promising compact source for high repetition-rate ultrafast spectroscopic applications.

Proceedings Article | 14 May 2018

1 μm-pumped optical parametric generator and oscillator based on orientation-patterned gallium phosphide

Hanyu Ye, S. Chaitanya Kumar, Junxiong Wei, P. Schunemann, M. Ebrahim-Zadeh

Proc. SPIE. 10684, Nonlinear Optics and its Applications 2018

KEYWORDS: Mid-IR, Optical parametric oscillators, Oscillators, Crystals, Signal generators, Nonlinear crystals, Gallium, Pulsed laser operation, Temperature metrology, Absorption

Read Abstract +

Proceedings Article | 15 February 2018

Femtosecond deep-infrared optical parametric oscillator pumped directly by a Ti:sapphire laser

Callum O'Donnell, Chaitanya Kumar S., Kevin Zawilski, Peter Schunemann, Majid Ebrahim-Zadeh

Proc. SPIE. 10516, Nonlinear Frequency Generation and Conversion: Materials and Devices XVII

KEYWORDS: Mid-IR, Optical parametric oscillators, Crystals, Laser applications, Nonlinear optics, Wavelength tuning, Ultrafast lasers, Nonlinear crystals

Read Abstract +

Proceedings Article | 15 February 2018

Performance characterization of mid-infrared difference frequency generation in orientation-patterned gallium phosphide

Junxiong Wei, Chaitanya Kumar S., Hanyu Ye, Peter Schunemann, M. Ebrahim-Zadeh

Proc. SPIE. 10516, Nonlinear Frequency Generation and Conversion: Materials and Devices XVII

KEYWORDS: Mid-IR, Optical parametric oscillators, Polarization, Crystals, Thermal effects, Laser crystals, Nonlinear crystals, Difference frequency generation

Read Abstract +

Proceedings Article | 15 February 2018

Advances in ultrafast optical parametric oscillators based on CdSiP2

Chaitanya Kumar S.

Proc. SPIE. 10516, Nonlinear Frequency Generation and Conversion: Materials and Devices XVII

KEYWORDS: Ultrafast phenomena, Mid-IR, Optical parametric oscillators, Femtosecond phenomena, Nd:YAG lasers, Semiconductor lasers, Signal processing, Picosecond phenomena, Pulsed laser operation, Absorption

Read Abstract +

Proceedings Article | 17 July 2014

The magic of light! An entertaining optics and photonics awareness program

Carlos Florensa, Míriam Martí, S. Chaitanya Kumar, Silvia Carrasco

Proc. SPIE. 9289, 12th Education and Training in Optics and Photonics Conference

KEYWORDS: Visualization, Graphene, Physics, Photonics, Nonlinear optics, Solids, Mathematics, Laser cutting, Prototyping, Quantum computing

Read Abstract +

DOWNLOAD PDF

Proceedings Article | 17 July 2014

Pick it up with light! An advanced summer program for secondary school students

Manoj Mathew, S. Kumar, Alejandra Valencia, Giorgio Volpe, Giovanni Volpe, Silvia Carrasco

Proc. SPIE. 9289, 12th Education and Training in Optics and Photonics Conference

KEYWORDS: Microscopes, Biomedical optics, Optical spheres, Particles, Physics, Optical tweezers, Objectives, Fractal analysis, Yeast, Geometrical optics

Read Abstract +

DOWNLOAD PDF

Proceedings Article | 16 May 2012

High-beam-quality narrow-linewidth 13W continuous-wave fiber-based source at 970 nm

Kavita Devi, S. Chaitanya Kumar, M. Ebrahim-Zadeh

Proc. SPIE. 8434, Nonlinear Optics and Applications VI

KEYWORDS: Second-harmonic generation, Continuous wave operation, Crystals, Fiber lasers, Semiconductor lasers, Thermal effects, Thulium, Laser crystals, Beam propagation method

Read Abstract +

Proceedings Article | 16 May 2012

Interferometeric output coupling of a continuous-wave optical parametric oscillator

Kavita Devi, S. Chaitanya Kumar, A. Esteban-Martin, M. Ebrahim-Zadeh

Proc. SPIE. 8434, Nonlinear Optics and Applications VI

KEYWORDS: Mirrors, Continuous wave operation, Optical parametric oscillators, Oscillators, Interferometers, Output couplers, Crystals, Fiber lasers, Ytterbium

Read Abstract +

Proceedings Article | 16 May 2012

Continuous-wave mode-locked optical parametric oscillator

Kavita Devi, S. Chaitanya Kumar, G. Samanta, A. Esteban-Martin, M. Ebrahim-Zadeh

Proc. SPIE. 8434, Nonlinear Optics and Applications VI

KEYWORDS: Mirrors, Continuous wave operation, Optical parametric oscillators, Modulation, Mode locking, Crystals, Phase shift keying, Picosecond phenomena, Electro optics

Read Abstract +

Proceedings Article | 11 May 2012

High-energy, tunable, mid-infrared, picosecond optical parametric generation in CdSiP2

S. Chaitanya Kumar, M. Jelínek, M. Baudisch, K. Zawilski, P. Schunemann, V. Kubecek, J. Biegert, M. Ebrahim-Zadeh

Proc. SPIE. 8434, Nonlinear Optics and Applications VI

KEYWORDS: Mid-IR, Optical parametric oscillators, Cadmium, Crystals, Silicon, Nd:YAG lasers, Nonlinear optics, Picosecond phenomena, Signal generators, Nonlinear crystals

Read Abstract +

Proceedings Article | 15 February 2012

High-energy 450-MHz CdSiP2 picosecond optical parametric oscillator near 6.3 μm for biomedical applications

S. Chaitanya Kumar, A. Agnesi, P. Dallocchio, F. Pirzio, G. Reali, K. Zawilski, P. Schunemann, M. Ebrahim-Zadeh

Proc. SPIE. 8240, Nonlinear Frequency Generation and Conversion: Materials, Devices, and Applications XI

KEYWORDS: Mid-IR, Energy efficiency, Mirrors, Optical parametric oscillators, Biomedical optics, Crystals, Nonlinear optics, Picosecond phenomena, Nonlinear crystals, Absorption

Read Abstract +

Proceedings Article | 23 August 2011

Continuous-wave-fiber-laser-pumped Ti:sapphire laser

Kavita Devi, S. Chaitanya Kumar, G. Samanta, M. Ebrahim-Zadeh

Proc. SPIE. 8173, Photonics 2010: Tenth International Conference on Fiber Optics and Photonics

KEYWORDS: Mirrors, Second-harmonic generation, Continuous wave operation, Output couplers, Crystals, Solid state lasers, Fiber lasers, Sapphire lasers, Laser damage threshold, Laser crystals

Read Abstract +

Proceedings Article | 23 August 2011

Highly efficient continuous-wave single-pass second-harmonic generation using multicrystal scheme

Kavita Devi, S. Chaitanya Kumar, G. Samanta, M. Ebrahim-Zadeh

Proc. SPIE. 8173, Photonics 2010: Tenth International Conference on Fiber Optics and Photonics

KEYWORDS: Mirrors, Second-harmonic generation, Continuous wave operation, High power lasers, Crystals, Quantum cascade lasers, Thermal effects, Laser crystals, Absorption

Read Abstract +

Proceedings Article | 23 September 2010

Performance and limitations of quasi-phase matching semiconductor waveguides with picosecond pulses

Sean Wagner, S. Chaitanya Kumar, Omid Kokabee, Barry Holmes, Usman Younis, Majid Ebrahim Zadeh, David Hutchings, Amr Helmy, J. Stewart Aitchison

Proc. SPIE. 7750, Photonics North 2010

KEYWORDS: Semiconductors, Second-harmonic generation, Optical parametric oscillators, Waveguides, Fiber lasers, Phase matching, Picosecond phenomena, Frequency conversion, Superlattices

Read Abstract +

Quasi-phase matched (QPM) second-order nonlinear optical processes in compound semiconductors are attractive for frequency conversion because of their large nonlinear susceptibilities and their mature fabrication processes that permit monolithic integration with pump lasers and other optical elements. Using quantum well intermixing (QWI), we have fabricated domain-disordered QPM (DD-QPM) waveguides in GaAs/AlGaAs superlattices and have previously demonstrated continuous-wave (CW) Type-I second-harmonic generation (SHG) and pulsed Type-II SHG. CW experiments were complicated by Fabry-Perot resonances and thermal bistability. Experiments using a 2-ps pulsed system were affected by third-order nonlinear effects, group-velocity mismatch (GVM), and poor spectral overlap with the conversion bandwidth. A better evaluation of the conversion efficiency may, however, be determined by using longer pulses in order to avoid these complications. By this, the effective CW conversion efficiency and χ<sup>(2)</sup> modulation can be ascertained. In this paper, we demonstrate SHG in DD-QPM waveguides with reduced parasitic effects by using 20 ps pulses. The waveguide structure consisted of a core layer of GaAs/Al<sub>0.85</sub>Ga0.15As superlattice into which QPM gratings with a period of 3.8 μm were formed using QWI by As<sup>2+</sup> ion implantation. For a Type-I phase matching wavelength of 1583.4 nm, average second-harmonic (SH) powers produced were as high as 2.5 μW for 2 ps pulses and 3.5 μW for 20-ps pulses. At low input powers, the SHG average power conversion efficiency of the 2-ps system was more than 10 times larger than the 20 ps system. As power was increased, the SH power saturated and conversion efficiency decreased to nearly equal to the 20-ps system which remained consistent over the same power range. This is attributed to a reduction in third-order nonlinear effects, a smaller pulse spectral width that overlaps better with the conversion bandwidth, and less pulse walkoff for the 20-ps pulses. Thus, by using 20-ps pulses over 2-ps pulses, we achieved similar output SH powers and potentially higher SH powers are possible since there was no observed saturation at high input power.

Proceedings Article | 5 June 2009

El Día de la Luz II (The Day of Light II): optics demonstration for high school students

Chaitanya S., Manoj Mathew, Giorgio Volpe, Osamu Takayama, Alejandra Valencia

Proc. SPIE. 9666, 11th Education and Training in Optics and Photonics Conference

KEYWORDS: Polarization, Glasses, Polarizers, Electroluminescence, Refraction, Photonic integrated circuits, Geometrical optics, Optics education, Light, Diffraction gratings

Read Abstract +

DOWNLOAD PDF

Showing 5 of 16 publications

Conference Committee Involvement (1)

Nonlinear Frequency Generation and Conversion: Materials and Devices XIX

3 February 2020 | San Francisco, California, United States

SIGN IN TO:

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Advertisement

Advertisement