Alexander Heifetz

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Recently, there has been a major thrust to understand biological processes at the nanoscale. Optical microscopy has been exceedingly useful in imaging cell microarchitecture. Characterization of cell organization at the nanoscale, however, has been stymied by the lack of practical means of cell analysis at these small scales. To address this need, we(More)
We report a means to detect deeply subwavelength pits in optical data-storage media by employing the recently observed giant backscattering perturbation phenomenon of the photonic jet. We conducted microwave experiments with dimensionally scaled-up pits and lands in a simulated optical data-storage device. These measurements were backed up by(More)
This paper reviews the substantial body of literature emerging since 2004 concerning photonic nanojets. The photonic nanojet is a narrow, high-intensity, non-evanescent light beam that can propagate over a distance longer than the wavelength λ after emerging from the shadow-side surface of an illuminated lossless dielectric microcylinder or microsphere of(More)
We theoretically investigate light scattering from a bi-sphere system consisting of a gold nanosphere and a lossless dielectric microsphere illuminated at a resonant optical wavelength of the microsphere. Using generalized multisphere Mie theory, we find that a gold nanosphere 100 times smaller than the dielectric microsphere can be detected with a(More)
Alexander Heifetz John T. Shen Jong-Kwon Lee Renu Tripathi M. S. Shahriar Northwestern University Department of Electrical and Computer Engineering Evanston, Illinois 60208 Abstract. We demonstrate a translation-invariant VanderLugt correlator VLC for a set of images stored via holographic angle multiplexing of volume gratings in a polymeric substrate. The(More)
We demonstrated a real-time shift-invariant VanderLugt correlator (VLC). The VLC was implemented with a 37 microm thick bis-triarylamine side-chain polymer matrix photorefractive (PR) polymer composite operating at 532 nm wavelength. Correlation selectivity was enhanced by real-time edge enhancement. The advantage of the VLC is that its architecture allows(More)
a Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, IL 60208, United States b Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, United States c CREOSA, Department of Physics & Pre-Engineering, Delaware State University, Dover, DE 19901, United States d Nuclear Engineering Division,(More)
We describe a subluminal laser which is extremely stable against perturbations. It makes use of a composite gain spectrum consisting of a broad background along with a narrow peak. The stability of the laser, defined as the change in frequency as a function of a change in the cavity length, is enhanced by a factor given by the group index, which can be as(More)
We demonstrate a high-speed inline holographic Stokesmeter that consists of two liquid crystal retarders and a spectrally selective holographic grating. Explicit choices of angles of orientation for the components in the inline architecture are identified to yield higher measurement accuracy than the classical architecture. We show polarimetric images of an(More)
We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can(More)