Professor of Physics, The City College of New York, 2007-present

Professor and Chair, Department of Physics, The City College of New York, 2016 - 2019

Associate Professor of Physics, The City College of New York, 2001 - 2006

Senior Member of Research Staff, IUSL The City College of New York, 1995 - 2001

Assistant Professor of Physics, Stevens Institute of Technology, 1988 - 1995

Research Associate, IUSL, The City College of NY 1984 - 1988

Swapan Kumar Gayen received his B. Sc. (Honors) and M. Sc. degrees in Physics from the University of Dacca, Bangladesh, in 1975 and 1977, respectively, and his Ph. D. in Physics from the University of Connecticut, Storrs, in 1984. He is currently a Professor of Physics at the City College and the Graduate Center of the City University of New York, and a member of the doctoral faculty of Physics and Electrical Engineering. His research interests are in optical biomedical imaging, imaging of targets in turbid media, tunable solid-state lasers, spectroscopy of impurity ions in solids, nonlinear optics, ultrafast laser spectroscopy, and optical spectroscopy and microscopy of nanoscale materials and composites. Dr. Gayen is a member of the American Physical Society, the Optical Society of America, and the New York Academy of Sciences.

• Ph. D., Physics, University of Connecticut, Storrs, 1984
• M. Sc., Physics, University of Dacca, Dacca, Bangladesh, 1977
• B. Sc. (Honors), University of Dacca, Dacca, Bangladesh, 1975 

• Physics 20700 University Physics I
• Physics 20800 University Physics II
• Physics 20900 University Physics III
• Physics 21900 Physics for Architecture Students
• Physics 32100 Modern Physics for Engineers
• Physics 32300 Quantum Mechanics for Applied Physicists
• Physics 37100 Advanced Physics Laboratory I
• Physics 47100 Advanced Physics Laboratory II
• Physics 55600 Current Topics in Physics

• Spectroscopy and microscopy of nanostructures
• Biomedical optical imaging
• Optical imaging and pulse propagation through turbid media
• Nanoscale photonic materials
• Tunable solid-state lasers
• Ultrafast lasers and spectroscopy
• Spectroscopy of impurity ion-doped solids
• Nonlinear optics

PUBLICATIONS

Selected Journal Articles

Pradip Kumar Bhowmik, Christina Inbok Lee, Jung Jae Koh, Haesook Han, Ahamed Jubair, Vladimir Kartazaev, Swapan Kumar Gayen, “Synthesis, optical and thermal properties of 2,4,6-tris(4-substituted phenyl)pyrylium tosylates and triflimides,” J. Mol. Struct. 1202 (2020) 127325. doi.org/10.1016/j.molstruc.2019.127325.

Jung Jae Koh, Christina Inbok Lee, Mihaela Alexa Ciulei, Haesook Han, Pradip Kumar Bhowmik, Vladimir Kartazaev, Swapan Kumar Gayen “Synthesis, optical spectroscopy and laser potential of pyrylium tosylates,” J. Mol Struct. 1171, 458 – 465 (2018). doi.org/10.1016/j.molstruc.2018.06.025

Binlin Wu, Mohammad Alrubaiee, S. K. Gayen, “Time reversal optical tomography: Detecting and locating tumors in an ex vivo model human breast,” Opt Laser Technol. 77, 229-235 (2016). DOI: 10.1016/joptlastec.2015.09.028
 

Joel De Jesus, Thor A. Garcia, Vladimir Kartazaev, Brynmor E. Jones, Peter J. Schlosser, Swapan K. Gayen, Jennifer E. Hastie, and Maria C. Tamargo, “Growth and characterization of ZnCdMgSe-based green light emitters and distributed Bragg reflectors towards II–VI based semiconductor disk lasers,” Phys. Status Solidi A 212, 382–389 (2015). DOI 10.1002/pssa.201431439.

Binlin Wu and S. K. Gayen, “Fluorescence tomography of targets in a turbid medium using nonnegative matrix factorization,” Phys. Rev. E 89, 042708 (2014).DOI: 10.1103/PhysRevE.89.042708.

Binlin Wu, W. Cai, S. K. Gayen, “Three-dimensional localization of fluorescent targets in turbid media using time reversal optical tomography,” Appl. Phys. Lett. 101, 251103 (2012).

Yimin Wang, S. K. Gayen, M. Alrubaiee, and R. R. Alfano, “Near-infrared center-of-intensity time gated imaging for detection of a target in a highly scattering turbid medium,” Technology in Cancer Research and Treatment 11, 309 - 315 (2012).
 

Yang Pu, Wubao Wang, M. Alrubaiee, S. K. Gayen, and M. Xu, “Determination of optical coefficients and fractal dimensional parameters of cancerous and normal prostate tissues,” Appl. Spectroscopy 66, 2012828-834 (2012).
 

Binlin Wu, M. Alrubaiee, W. Cai, M. Xu, and S. K. Gayen, “Diffuse optical imaging using decomposition methods,” International J. Opt. 2012, Article ID 185435, 12 pages (2012); doi:10.1155/2012/185435.
 

Binlin Wu, W. Cai, M. Alrubaiee, M. Xu, and S. K. Gayen, “Time reversal optical tomography: locating targets in a highly scattering turbid medium,” Opt. Express 19, 21956-21976 (2011).
 

W. Cai and S. K. Gayen, “Retrieval of water cloud characteristic from active sensor data using the analytical solution of radiative transfer equation,” JQSRT 111, 226 (2010).
 

M. Xu, M. Alrubaiee, S. K. Gayen and R. R. Alfano, “Optical diffuse imaging of an ex vivo model cancerous human breast using independent component analysis,” IEEE J. Select. Topics Quantum Electron. 14, 43 (2008).
 

S. K. Gayen, C. Gonzalez, V. Balogh-Nair, M. Brito, B. B. Das, G. Comanescu, X. C. Liang, A. H. Byro, David. L. V. Bauer, M. Alrubaiee, and R. R. Alfano, “Optical Spectroscopy of a Hybrid CdS-Dendrimer Nanocomposite,” J. Opt. Soc. Am. B 24, 3064 (2007). Selected and published in Vol. 3 Issue 1 (January 29, 2008) of the Virtual Journal for Biomedical Optics (VJBO).  http://vjbo.osa.org/virtual_issue.cfmhttp://www.opticsinfobase.org/abst…
 

W. Cai, Xiaohui Ni, S. K. Gayen and R. R. Alfano, “Analytical cumulant solution of the vector radiative transfer equation investigates backscattering of circularly polarized light from turbid media,” Phys. Rev. E 74, 056605 (2006).
 

M. Alrubaiee, M. Xu, S. K. Gayen, and R. R. Alfano, “Three-dimensional localization and cross section reconstruction of fluorescent targets in ex vivo breast tissue using independent component analysis,” Appl. Phys. Lett. 89, 133902 (2006).
 

M. Alrubaiee, M. Xu, S. K. Gayen, M. Brito, and R. R. Alfano, “Three-dimensional optical tomographic imaging of objects in tissue-simulating turbid medium using independent component analysis,” Appl. Phys. Lett. 87, 191112 (2005).
 

M. Alrubaiee, S. K. Gayen, R. R. Alfano, and J. A. Koutcher, “Spectral and temporal near-infrared imaging of ex vivo cancerous and normal human breast tissues,” Technology in Cancer Research and Treatment 4, 455-482 (2005).
 

M. Xu, M. Alrubaiee, S. K. Gayen and R. R. Alfano, “Three-dimensional optical imaging of objects in a turbid medium using independent component analysis: simulational study,” J. Biomed. Opt. 10, 051705 (2005).
 

M. Xu, M. Alrubaiee, S. K. Gayen and R. R. Alfano, “Three-dimensional localization and optical imaging of objects in turbid media using independent component analysis,” Appl. Opt. 44, 1889 (2005).
 

M. E. Zevallos, S. K. Gayen, M. Alrubaiee, and R. R. Alfano, “Time-gated backscattered ballistic light imaging of objects in turbid water,” Appl. Phys. Lett. 86, 011115 (2005).
 

S. K. Gayen, M. Alrubaiee, H. E. Savage, S. P. Schantz, and R. R. Alfano, “Parotid gland tissues investigated by picosecond time-gated and spectroscopic imaging techniques,” IEEE J. Select. Topics Quantum Electron. 7, 906 (2001).
 

S. K. Gayen, M. E. Zevallos, and R. R. Alfano, "Near-infrared laser spectroscopic imaging: a step towards diagnostic optical imaging of human tissues," Lasers Life Sci. 8, 187 (1999).
 

W. Cai, S. K. Gayen, M. Xu, M. Zevallos, M. Alrubaiee, M. Lax, and R. R. Alfano, "Optical three-dimensional inverse image reconstruction of objects in turbid media from ultrafast time-sliced optical transmission measurements," Appl. Opt. 38, 4237 (1999).
 

S. K. Gayen and R. R. Alfano, “Sensing lesions in tissues with light,” Opt. Express 4, 475 (1999).
 

M. Zevallos, S. K. Gayen, B. B. Das, M. Alrubaiee, R. R. Alfano, “Picosecond electronic time-gated imaging of bones in tissues,” IEEE J. Select. Topics Quantum Electron. 5, 916 (1999).
 

S. K. Gayen, M. E. Zevallos, M. Alrubaiee, J. M. Evans, and R. R. Alfano, "Two-dimensional near-infrared transillumination imaging of biomedical media with a chromium-doped forsterite laser," Appl. Opt. 37, 5327 (1998).
 

Q. Fu, F. Seier, S. K. Gayen, and R. R. Alfano, "A high-average-power, kilohertz-repetition-rate, sub-100-fs Ti:sapphire amplifier system," Opt. Lett. 22, 712 (1997).
 

K. E. Gonsalves, G. Carlson, X. Chen, S. K. Gayen, R. Perez, M. Jose-Yacaman, "Synthesis and nonlinear optical characterization of nanostructured gold/polymer composites and suspensions," Nanostructured Materials 7, 293 (1996).
 

R. I. Billmers, S. K. Gayen, M. F. Squicciarini, V. M. Contarino., W. J. Scharpf, and D. A. Alocca, "Experimental demonstration of an excited-state Faraday filter at 532 nm," Opt. Lett. 20, 106 (1995).
 

S. K. Gayen, R. I. Billmers, Guangning Yang, V. M. Contarino, M. F. Squicciarini, D. M. Alocca, W. J. Scharpf, and P. R. Herczfeld, "Induced-dichroism excited atomic line filter at 532 nm," Opt. Lett. 20, 1427 (1995).
 

Y. M. Cheung and S. K. Gayen, "Optical nonlinearities of tea studied by the Z-scan and the four wave-mixing techniques," J. Opt. Soc. Am. B 11, 636 (1994).
 

Y. M. Cheung and S. K. Gayen, "Excited-state absorption in Pr³⁺:Y₃Al₅O₁₂," Phys. Rev. B 49, 14 827 (1994).
 

G. S. Nolas, V. G. Tsoukala, S. K. Gayen, and Glen A. Slack, "Electronic-Raman-scattering study of the low-lying energy-levels of trivalent cerium-doped yttria," Phys. Rev. B 50, 150 (1994).
 

G. S. Nolas, V. G. Tsoukala, S. K. Gayen, and Glen A. Slack, "Site-selective electronic Raman excitation spectroscopy of the lowest 4f --> 5d transitions in Ce³⁺:Y₂O₃," Opt. Lett. 19, 1574 (1994).

Bin Qing Xie and S. K. Gayen, "Resonance enhancement of two-photon transitions to the second excited 4f5d state in Pr³⁺:Y₃Al₅O₁₂," Phys. Rev. B 47, 5557 (1993).

S. K. Gayen, Bin Qing Xie, and Y. M. Cheung, "Two-photon excitation of the lowest 4f² --> 4f5d near-ultraviolet transitions in Pr³⁺:Y₃Al₅O₁₂," Phys. Rev. B 45, 20 (1992).

V. Petricevic, S. K. Gayen, and R. R. Alfano, "Continuous-wave laser operation of chromium-doped forsterite," Opt. Lett. 14, 612 (1989).

D. S. Hamilton, S. K. Gayen, G. J. Pogatshnik, R. D. Ghen, and W. J. Miniscalco, "Optical absorption and photoionization measurements from the excited states of Ce³⁺:Y₃Al₅O₁₂," Phys. Rev. B 39, 8807 (1989).

V. Petricevic, S. K. Gayen, R. R. Alfano, K. Yamagishi, and K. Moriya, "Laser action in chromium-doped forsterite," Appl. Phys. Lett. 52, 1040 (1988).
 

V. Petricevic, S. K. Gayen, and R. R. Alfano, "Laser action in chromium-activated forsterite for near-infrared excitation: is Cr⁴⁺ the lasing ion?" Appl. Phys. Lett. 53, 2590 (1988).
 

S. K. Gayen, W. B.Wang, V. Petricevic, K. M. Yoo, and R. R. Alfano, "Picosecond excite-and-probe absorption measurement of intra-2EgE3/2-state vibrational relaxation time in Ti³⁺: Al₂O₃," Appl. Phys. Lett. 50, 1494 (1987).
 

S. K. Gayen, W. B. Wang, V. Petricevic, and R. R. Alfano, "Nonradiative transition dynamics in alexandrite," Appl. Phys. Lett. 49, 437 (1986).
 

S. K. Gayen, D. S. Hamilton, and R. H. Bartram, "Analysis of the lowest 4f-->5d two-photon transition in Ce³⁺:CaF₂," Phys. Rev. B 34, 7517 (1986).
 

S. K. Gayen, W. B. Wang, V. Petricevic, R. Dorsinville, and R. R. Alfano, "Picosecond excite-and-probe absorption measurement of the ⁴T₂-state nonradiative lifetime in ruby," Appl. Phys. Lett. 47, 455 (1985).
 

S. K. Gayen and D. S. Hamilton, "Two-photon excitation of the lowest 4f-->5d near-ultraviolet transitions in Ce³⁺:CaF₂," Phys. Rev. B 28, 3706 (1983).
 

Patents

Binlin Wu, Wei Cai, and Swapan K. Gayen, “Time reversal optical tomography for locating targets in a highly scattering turbid medium,” US patent Number: 9,867,542B2 awarded January 16, 2018.
 

R. R. Alfano, Min Xu, Mohammed Alrubaiee, and S. K. Gayen, “Optical tomography using independent component analysis for detection and localization of targets in turbid media,” U. S. Patent Number: 7,826,878 B2 awarded November 2, 2010.
 

R. R. Alfano, J. Ying, W. Cai, and S. K. Gayen, "Methods of improving line-of-sight wireless optical communication through adverse environmental conditions," U. S. Patent Number: 7,106,972 awarded September 12, 2006.
 

R. R. Alfano, S. K. Gayen, and M. E. Zevallos, "Spectroscopic and time-resolved optical methods and apparatus for imaging objects in turbid media,” U. S. Patent Number: 6,665,557 B1 awarded December 16, 2003.
 

R. R. Alfano, W. Cai, and S. K. Gayen, "Time-resolved diffusion tomographic 2D and 3D imaging in highly scattering turbid media," U. S. Patent Number: 6,108,576 awarded August 22, 2000.
 

R. I. Billmers, S. K. Gayen, and M. F. Squicciarini, "Excited-State Polarization Altering Filter," U. S. Patent Number: 5,721,632 awarded February 24, 1998.
 

R. R. Alfano, V. Petricevic, and S. K. Gayen, "Chromium-doped forsterite laser system," U. S. Patent Number: 4,932,031 awarded June 5, 1990.