Physical Optics and Electronics Group
Prof. Rajeev Ram


  1. Z. Li, J. Xue, M. de Cea, J. Kim, H. Nong, D. Chong, K. Yong Lim, E. Quek, & R. J. Ram, "A sub-wavelength Si LED integrated in a CMOS platform," Nature Communications 14, no. 1 (2023): 882, DOI: [PDF] Link to Publication
  2. I. Kang, M. de Cea, J. Xue, Z. Li, G. Barbastathis, & R. J. Ram, "Simultaneous spectral recovery and CMOS micro-LED holography with an untrained deep neural network," Optica 9, no. 10 (2022): 1149-1155, DOI: [PDF] Link to Publication
  3. K. X. E. Kay, A. H. Atabaki, W. Bo Ng, Z. Li, G. P. Singh, S. W. L. Tan, & R. J. Ram, "Identification of illicit street drugs with swept‐source Raman spectroscopy," Journal of Raman Spectroscopy 53, no. 7 (2022): 1321-1332, DOI: [PDF] Link to Publication
  4. Z. Li, N. Persits, D. J. Gray Jr., & R. J. Ram, "Computational polarized Raman microscopy on sub-surface nanostructures with sub-diffraction-limit resolution," Optics Express 29, no. 23 (2021): 38027-38043, DOI: [PDF] Link to Publication
  5. P. Joong Chung, G. P. Singh, C-H. Huang, S. Koyyappurath, J. Sung Seo, H-Z. Mao, P. Diloknawarit, R. J. Ram, R. Sarojam, & N-H. Chua, "Rapid Detection and Quantification of Plant Innate Immunity Response Using Raman Spectroscopy," Frontiers in Plant Science 12 (2021): 746586, DOI: [PDF] Link to Publication
  6. A. H. Atabaki, W. F. Herrington, C. Burgner, V. Jayaraman, & R. J. Ram, "Low-power swept-source Raman spectroscopy," Optics Express, vol 29, issue 16 (2021) DOI: [PDF] Link to Publication
  7. J. Xue , J. Kim, A. Mestre, K. M. Tan, D. Chong, S. Roy, H. Nong, K. Y. Lim, D. Gray, D. Kramnik, A. Atabaki, E. Quek, & R. J. Ram, "Low-Voltage, High-Brightness Silicon Micro-LEDs for CMOS Photonics," IEEE Transactions on Electron Devices, vol 68, Issue 8 (2021): 3870 - 3875, DOI: [PDF] Link to Publication
  8. N. Persits, J. Kim, D. Gray, Z. Li, A. H. Atabaki, & R. J. Ram , "Networked Swept-Source Raman Sensors," OSA Technical Digest (Optica Publishing Group) (2021) DOI: [PDF] Link to Publication
  9. M. de Cea, A. H. Atabaki, & R. J. Ram, "Energy harvesting optical modulators with sub-attojoule per bit electrical energy consumption," Nature, Nature Communications 12 (2021): 2326, DOI: [PDF] Link to Publication
  10. M. de Cea, D. Van Orden, J. Fini, M. Wade, & R. J. Ram, "High-speed, zero-biased silicon-germanium photodetector," APL Photonics, vol 6, issue 4 (2021): 041302 , DOI: [PDF] Link to Publication
  11. G. N. West, W. Loh, D. Kharas, & R. J. Ram, "Impact of laser frequency noise on high-extinction optical modulation," Optics Express 28, no. 26 (2020): 39606-39617, DOI: [PDF] Link to Publication
  12. T. T. S. Lew, R. Sarojam, I. C. Jang, B. S. Park, N. I. Naqvi, M. H. Wong, G. P. Singh, R. J. Ram, O. Shoseyov, K. Saito, N. H. Chua, & M. S. Strano, "Species-independent analytical tools for next-generation agriculture," Nature Plants (2020): 1-10, DOI: [PDF] Link to Publication
  13. S. Gupta, C. H. Huang, G. P. Singh, B. S. Park, N. H. Chua & R. J. Ram, "Portable Raman leaf-clip sensor for rapid detection of plant stress," Scientific Reports, 10(1) (2020): 1-10, DOI: [PDF] Link to Publication
  14. B. J. R. Sng, G. P. Singh, K. Van Vu, N. H. Chua, R. J. Ram, & I. C. Jang , "Rapid metabolite response in leaf blade and petiole as a marker for shade avoidance syndrome," Plant methods, 16(1) (2020): 1-17, DOI: [PDF] Link to Publication
  15. M. de Cea, E. E. Wollman, A. H. Atabaki, D. J. Gray, M. D. Shaw & R. J. Ram, "Photonic Readout of Superconducting Nanowire Single Photon Counting Detectors," Nature, Scientific Reports, 10 (2020): 9470, DOI: [PDF] Link to Publication
  16. C. H. Huang, G. P. Singh, S. H. Park, N. H. Chua, R. J. Ram, & B. S. Park, "Early Diagnosis and Management of Nitrogen Deficiency in Plants Utilizing Raman Spectroscopy," Frontiers in Plant Science, 11 (2020): 663, DOI: [PDF] Link to Publication
  17. N. Han, & R. J. Ram, "Bayesian Modeling and Computation for Analyte Quantification in Complex Mixtures Using Raman Spectroscopy," Computational Statistics & Data Analysis, vol. 143 (2020): 106846, DOI: [PDF] Link to Publication
  18. Z. Li, J. Xue, & R. J. Ram, "Heat exchange with interband tunneling," Journal of Applied Physics (2019): 165107, DOI: [PDF] Link to Publication
  19. N. Han, G. N. West, A. H. Atabaki, D. Burghoff, & R. J. Ram, "Compact and high-precision wavemeters using the Talbot effect and signal processing," Optics letters 44, no. 17 (2019): 4187-4190, DOI: [PDF] Link to Publication
  20. M. de Cea, A. H. Atabaki, & R. J. Ram, "Power handling of silicon microring modulators," Opt. Express 27 (2019): 24274-24285 , DOI: [PDF] Link to Publication
  21. G. West, W. Loh, D. Kharas, C. Sorace-Agaskar, K. K. Mehta, J. Sage, J. Chlaverini, & R. J. Ram, "Low-loss integrated photonics for the blue and ultraviolet regime," APL Photonics (2019) DOI: [PDF] Link to Publication
  22. V. Mehra, R. Amatya, & R. J. Ram, "Estimating the value of demand-side management in low-cost, solar micro-grids," Energy, 163 (2018): 74-87, DOI: [PDF] Link to Publication
  23. V. Stojanović, R. J. Ram, M. Popović, S. Lin, S. Moazeni, M. Wade, C. Sun, L. Alloatti, A. H. Atabaki, F. Pavanello, N. Mehta, & P. Bhargava, "Monolithic silicon-photonic platforms in state-of-the-art CMOS SOI processes," Optics Express, Vol. 26, No. 10 (2018) DOI: [PDF] Link to Publication
  24. A. H. Atabaki, S. Moazeni, F. Pavanello, H. Gevorgyan, J. Notaros, L. Alloatti, M. T. Wade, C. Sun, S. A. Kruger, H. Meng, K. Al Qubaisi, I. Wang, B. Zhang, A. Khilo, C. V. Baiocco, M. A. Popović, V. M. Stojanović & R. J. Ram, "Integrating photonics with silicon nanoelectronics for the next generation of systems on a chip," Nature, 556 (2018): 349-354, DOI: [PDF] Link to Publication
  25. W. F. Herrington Jr., G. P. Singh, D. Wu, P. W. Barone, W. Hancock & R. J. Ram, "Optical Detection of Degraded Therapeutic Proteins," Scientific Reports, 8:5098 (2018) DOI: DOI:10.1038/s41598-018-23409-z [PDF] Link to Publication
  26. S. Moazeni, S. Lin, M. Wade, L. Alloatti, R. J. Ram, & M. Popović, V. Stojanović, "A 40-Gb/s PAM-4 Transmitter Based on a Ring-Resonator Optical DAC in 45-nm SOI CMOS," IEEE Journal of Solid-State Circuits Vol: 52, Issue 12, Dec 2017 (2017) DOI: 10.1109/JSSC.2017.2748620 [PDF] Link to Publication
  27. J. Xue, Z. Li, & R. J. Ram, "Irreversible Thermodynamic Bound for the Efficiency of Light-Emitting Diodes," American Physical Society, Physical Review Applied, 8, 014017 (2017) DOI: 10.1103/PhysRevApplied.8.014017 [PDF] Link to Publication
  28. K. Mehta, & R. J. Ram, "Precise and diffraction-limited waveguide-to-free-space focusing gratings," Nature, Scientific Reports, 7, Article Number: 2019 (2017) (2017) DOI: 10.1038/s41598-017-02169-2 [PDF] Link to Publication
  29. A. Atabaki, H. Meng, L. Alloatti, K. Mehta, & R. J. Ram, "High-speed polysilicon CMOS photodetector for telecom and Datacom," Applied Physics Letters (2016): 109, 111106 (2016), DOI: 10.1063/1.4962641 [PDF] Link to Publication
  30. L. Alloatti, & R. J. Ram, "Infrared vertically-illuminated photodiode for chip alignment feedback," AIP Advances (2016): 6, 085219 (2016), DOI: 10.1063/1.4961949 [PDF] Link to Publication
  31. K. Mehta, C. Bruzewicz, R. McConnell, R. J. Ram, J. Sage, & J. Chiaverini, "Integrated optical addressing of an ion qubit," Nature Nanotechnology (2016) DOI: 10.1038/NNANO.2016.139 [PDF] Link to Publication
  32. P. Perez-Pinera, N. Han, S. Cleto, J. Cao, O. Purcell, K. A. Shah, K. Lee, R. J. Ram, & T. K. Lu, "Synthetic biology and microbioreactor platforms for programmable production of biologics at the point-of-care," Nature Communications (2016) DOI: 10.1038/ncomms12211 [PDF] Link to Publication
  33. N. Han, S. Cho, A. Atabaki, E. Ye, W. Herrington, & R. J. Ram , "Non-paraxial Talbot Effect for Building Compact Spectrometers," Computational Optical Sensing and Imaging (COSI), Heidelberg, Germany (2016) [PDF] Link to Publication
  34. E. Ye, A. Atabaki, N. Han, & R. J. Ram, "Miniature, sub-nanometer resolution Talbot spectrometer," Optics Letters, V. 41, 11 (2016): 2434-2437, [PDF] Link to Publication
  35. L. Alloatti, D. Cheian, & R. J. Ram, "High-speed modulator with interleaved junctions in zero-change CMOS photonics," Applied Physics Letters, 108, 131101 (2016) DOI: 10.1063/1.4944999 [PDF] Link to Publication
  36. L. Alloatti, & R. J. Ram, "Resonance-enhanced waveguide-coupled silicon-germanium detector," Applied Physics Letters (2016): 108, 071105 , DOI: 10.1063/1.4941995 [PDF] Link to Publication
  37. C. Sun, M. Wade, Y. Lee, J. Orcutt, L. Alloatti, M. Georgas, A. Waterman, J. Shainline, R. Avizienis, S. Lin, R. Kumar, F. Pavanello, A. Atabaki, H. Cook, A. Ou, B. Moss, J. Leu, Y-H. Chen, K. Asanovic, R. Ram, M. Popovic, & V. Stojanovic , "Single-Chip Microprocessor with Integrated Photonic I/O," Nature (2015): v. 528, pp 534–538, DOI: 10.1038/nature16454 [PDF] Link to Publication
  38. H. Meng, A. Atabaki, J. Orcutt, & R. Ram, "Sub-bandgap polysilicon photodetector in zero-change CMOS process for telecommunication wavelength," Optics Express (2015): 23, 32643-32653 , DOI: 10.1364/OE.23.032643 [PDF] Link to Publication
  39. J. Xue, Y. Zhao, S. Oh, W. Herrington, J. Speck, S. DenBaars, S. Nakamura, & R. J. Ram, "Thermally enhanced blue light-emitting diode," Applied Physics Letters (2015): 107, DOI: 10.1063/1.4931365 [PDF] Link to Publication
  40. L. Alloatti, S. A. Srinivasan, J. S. Orcutt, & R. J. Ram, "Waveguide-coupled detector in zero-change complementary metal–oxide–semiconductor," Appl. Phys. Lett. 107, 041104 (2015) DOI: [PDF] Link to Publication
  41. C. Sun, M. Wade, M. Georgas , S. Lin , L. Alloatti , B. Moss , R. Kumar, A. H. Atabaki , F. Pavanello , R. J. Ram , M. Popović , & V. Stojanović , "A 45nm SOI Monolithic Photonics Chip-to-Chip Link with Bit-Statistics-Based Resonant Microring Thermal Tuning," VLSI Symposium (2015) [PDF] Link to Publication
  42. N. J. Mozdzierz, K. R. Love, K. S. Lee, H. L. T. Lee, K. A. Shah, R. J. Ram, & J. C. Love, "A perfusion-capable microfluidic bioreactor for assessing microbial heterologous protein production," Lab on a Chip (2015): 15, 2918-2922, DOI: 10.1039/C5LC00443H [PDF] Link to Publication
  43. L. Alloatti, M. Wade, V. Stojanovic, M. Popovic, & R. J. Ram, "Photonics design tool for advanced CMOS nodes," IET Optoelectronics, Vol. 9, Iss. 4, (2015): 163–167, DOI: 10.1049/iet-opt.2015.0003 [PDF] Link to Publication
  44. G. P. Singh, S. Goh, M. Canzoneri, & R. J. Ram, "Raman Spectroscopy of Complex Defined Media: Biopharmaceutical Applications," Journal of Raman Spectroscopy (2015) DOI: 10.1002/jrs.4686 [PDF] Link to Publication
  45. C. Sun, M. Georgas, J. Orcutt, B. Moss, Y.-H. Chen, J. Shainline, M. Wade, K. Mehta, K. Nammari, E. Timurdogan, D. Miller, O. Tehar-Zahav, Z. Sternberg, J. Leu, J. Chong, R. Bafrali, G. Sandhu, M. Watts, R. Meade, M. Popovic, R. J. Ram, & V. Stojanovic, "A Monolithically-Integrated Chip-to-Chip Optical Link in Bulk CMOS," IEEE J. of Solid-State Circuits 50.4 (2015): 828-844, DOI: 10.1109/JSSC.2014.2382101 [PDF] Link to Publication
  46. K. K. Mehta, A. M. Eltony, C. D. Bruzewicz, I. L. Chuang, R. J. Ram, J. M. Sage, & J. Chiaverini, "Ion Traps Fabricated in a CMOS Foundry," Applied Physics Letters (2014) [PDF] Link to Publication
  47. N. Han, O. Purcell, K. S. Lee, T. K. Lu, & R. J. Ram, "Microfluidics for Control in Synthetic Biology," MicroTAS, San Antonio, TX (2014) [PDF] Link to Publication
  48. D. Huang, P. Santhanam, & R. J. Ram, "Low-Power Communication with a Photonic Heat Pump," Optics Express, 22, S7 (2014): A1650-58, [PDF] Link to Publication
  49. K. K. Mehta, A. M. Eltony, C. D. Bruzewicz, I. L. Chuang, R. J. Ram, J. M. Sage, & J. Chiaverini, "Ion Traps Fabricated in a CMOS Foundry," Applied Physics Letters 105, 044103 (2014) DOI: [PDF] Link to Publication
  50. K. K. Mehta, J. S. Orcutt, J. M. Shainline, O. Tehar-Zahav, Z. Sternberg, R. Meade, M. A. Popović, & R. J. Ram, "Polycrystalline Silicon Ring Resonator Photodiodes in a Bulk Complementary Metal-Oxide-Semiconductor Process," Optics Letters 39, 4 (2014): 1061-4, [PDF] Link to Publication
  51. W. Loh, S. Yegnanarayanan, R. J. Ram, & P. Juodawlkis, "A Nonlinear Optoelectronic Filter for Electronic Signal Processing," Nature Scientific Reports 4, 3613 (2014) [PDF] Link to Publication
  52. D. J. Gray, Jr, P. Santhanam, & R. J. Ram, "Design for Enhanced Thermo-Electric Pumping in Light Emitting Diodes," Applied Physics Letters 103.12 (2013): 123503, DOI: 10.1063/1.4821266 [PDF] Link to Publication
  53. S. Chen, S. Lee, H. Lo, Y. Hung, K. Lee, C. Tu, Y. Pan, & R. J. Ram, "Silicon Platform with Vertically Aligned Carbon Nanotubes for Enhancing Thermal Conduction in Hybrid Optoelectronic Integration," IEEE Trans. Compon. Packag. Manuf. Technol. 2.7 (2012): 1128-34, [PDF] Link to Publication
  54. J. Bahk, P. Santhanam, Z. Bian, R. J. Ram, & A. Shakouri, "Resonant Carrier Scattering by Core-Shell Nanoparticles for Thermoelectric Power Factor Enhancement," Applied Physics Letters 100 (2012) DOI: 10.1063/1.3673615 [PDF] Link to Publication