Area of Study / Keywords
Photonics and Plasmas
Dr. Porat received his BSc and PhD degrees in Electrical and Electronics Engineering from Tel Aviv University in 2007 and 2014, respectively. During his PhD he theoretically developed nonlinear optics analogues to coherent atomic processes and demonstrated them experimentally, facilitating novel phenomena attractive for optical frequency conversion, including adiabatic frequency conversion. He also developed the Airy beam laser and generalized adiabatic nonlinear optics.
Dr. Porat spent two years as a postdoctoral fellow at the Weizmann Institute of Science, and three years as a research associate at JILA. At the Weizmann Institute he used ultrafast and nonlinear optics methods, together with a strong-field physics technique called electron holography, to resolve the attosecond-scale temporal properties of the quantum tunneling process. His research at JILA was centered on the development of the extreme ultraviolet frequency comb laser. His work made it possible to overcome effects detrimental to extreme ultraviolet generation, and achieve record power levels.
My research is centered on the development of infrared, visible and ultraviolet frequency combs (stabilized pulsed lasers) and their uses in fundamental physics, industry and medical applications. Long term goals of my research plan include achieving highly sensitive magnetometry and direct optical nuclear spin polarization of noble gases. Highly sensitive magnetometry would make it possible to realize nuclear magnetic resonance (NMR) spectroscopy without the use of large facility scale equipment. The same magnetometric technique could also be used to search for new physics, e.g., by testing general relativity or searching for dark matter. Direct optical nuclear spin polarization (hyperpolarization) of noble gases would remove a major bottleneck for advancing pulmonary MRI and quantum magnetometry. I also explore other applications of the lasers developed in my research, such as environmental sensing, material processing and semiconductor device fabrication, metrology and inspection, as well as creating tabletop alternatives to large, particle accelerator based ultraviolet sources such as synchrotrons and free electron lasers.
The techniques I use and develop span a wide range of disciplines, including ultrafast and nonlinear optics, laser stabilization, high power fiber lasers and amplifiers, atomic spectroscopy and coherent control.
Introduction to linear systems and signal classification. Delta function and convolution. Fourier series expansion. Fourier transform and its properties. Laplace transform. Analysis of linear time invariant (LTI) systems using the Laplace transform. Prerequisites: ECE 202 or E E 240, MATH 201. Credit may be obtained in only one of ECE 240 or E E 238.
Interaction of radiation with atoms, laser oscillations and threshold conditions, 3- and 4-level laser systems, rate equations, special properties of laser light, cavity Q and photon lifetime, optical resonators and lens waveguides, Gaussian beams, gain saturation, Q-switching, mode locking, interaction of light and sound, holography. Description of various lasers: solid, gas, semiconductor, dye, Raman and chemical. Laser applications. Prerequisites: ECE 370 or E E 315 or PHYS 381 or consent of Instructor. Credit may be obtained in only one of ECE 472 or E E 472.
Fundamental description of nonlinear optical phenomena in terms of higher order susceptibilities, quantum theory of nonlinear susceptibility, density matrix approach, rabi oscillations, optical bloch equations, Various specific nonlinear phenomena: electro-optic modulation, acousto-optic modulation, harmonic generation and frequency conversion, stimulated Raman and Brillouin scattering and amplification, parametric oscillation and amplification, self phase modulation, soliton propagation, and photorefractive effects, Applications to optical switching.