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The resolution of optical imaging devices is ultimately limited by the diffraction of light. To circumvent this limit, modern super-resolution microscopy techniques employ active interaction with the object by exploiting its optical…

Optics · Physics 2022-01-05 A. A. Pushkina , G. Maltese , J. I. Costa-Filho , P. Patel , A. I. Lvovsky

MR images have a magnitude and a phase, but in almost all clinical applications only the magnitude images are used, because the phase images have a smooth but strong background signal that masks useful information. The phase contains…

Numerical Analysis · Mathematics 2017-12-27 Wolfgang Stefan , David Fuentes , Erol Yeniaras , Ken-Pin Hwang , John D. Hazle , R. Jason Stafford

Photo-acoustic spectroscopy (PAS) is one of the most sensitive non-destructive analysis techniques for gases, fluids and solids. It can operate background-free at any wavelength and is applicable to microscopic and even non-transparent…

Optical coherence tomography (OCT) has proven to be a powerful technique for studying tissue morphology in ophthalmology, cardiology, and endomicroscopy. Its performance is limited by the fundamental trade-off between the imaging…

Optics · Physics 2008-02-27 Keisuke Goda , Daniel R. Solli , Bahram Jalali

We introduce an approach for performing spectrally resolved electron microscopy without the need for an electron spectrometer. The method involves an electron beam prepared as a coherent superposition of multiple paths, one of which passes…

Materials Science · Physics 2025-04-24 F. Javier García de Abajo , Cruz I. Velasco

We propose an optical encryption framework that can encrypt and decrypt large-sized images beyond the size of the encrypted image using our two methods: random phase-free method and scaled diffraction. In order to record the entire image…

The detection of ultrafast optical and radio-frequency (RF) signals is crucial for applications ranging from high-speed communications to advanced sensing. However, conventional detectors are fundamentally constrained by their intrinsic…

An optical cavity consisting of optically trapped mirrors makes a resonant bar that can be stiffer than diamond. A limitation of the stiffness arises in the length of the optical bar as a consequence of the finite light speed. High laser…

Optics · Physics 2020-07-06 K. Somiya , J. Kato , K. Yano , N. Saito

Pump-probe microscopy enables label-free imaging of structural and chemical features of samples. However, signals in pump-probe microscopy are typically small and often must be measured in the presence of large backgrounds. As a result,…

We use the phenomenon of electromagnetically-induced transparency in a three-level atomic system for hyperfine spectroscopy of upper states that are not directly coupled to the ground state. The three levels form a ladder system: the probe…

Optics · Physics 2007-05-23 Anusha Krishna , Kanhaiya Pandey , Ajay Wasan , Vasant Natarajan

High-gain optical parametric amplification is an important nonlinear process used both as a source of coherent infrared light and as a source of nonclassical light. In this work, we experimentally demonstrate an approach to optical…

This paper presents a robust regression approach for image binarization under significant background variations and observation noises. The work is motivated by the need of identifying foreground regions in noisy microscopic image or…

Computer Vision and Pattern Recognition · Computer Science 2018-07-18 Garret Vo , Chiwoo Park

Confocal Raman microscopy, a highly specific and label-free technique for the microscale study of thick samples, often presents difficulties due to weak Raman signals. Inhomogeneous samples introduce wavefront aberrations that further…

The contrast of an image can be degraded by the presence of background light and sensor noise. To overcome this degradation, quantum illumination protocols have been theorised (Science 321 (2008), Physics Review Letters 101 (2008)) that…

Quantum Physics · Physics 2021-09-21 Thomas Gregory , Paul-Antoine Moreau , Ermes Toninelli , Miles J. Padgett

Atomic Force Microscopy - Infrared (AFM-IR) has emerged as a useful technique for measuring absorption spectra with spatial resolution better than the optical diffraction limit. The technique relies on the movement of a probe for atomic…

Applied Physics · Physics 2024-01-17 Luca Quaroni

In the process of parametric optical image amplification, images are formed at new frequencies in addition to the amplified original image. We show that the parametric multiplexing of optical images can be used to produce an image with…

Quantum Physics · Physics 2019-03-27 D. A. Balakin , A. S. Chirkin

Tendencies in five main branches of atomic spectrometry (absorption, emission, mass, fluorescence and ionization spectrometry) are considered. The first three techniques are the most widespread and universal, with the best sensitivity…

Instrumentation and Detectors · Physics 2007-05-23 A. A. Bol'shakov , A. A. Ganeev , V. M. Nemets

We propose a cross-correlation method for the searches of ultra-light fields, in particular, with a space network of atomic sensors. The main motivation of the approach is cancellation of uncorrelated noises in the observation data and…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-01 Tigran Kalaydzhyan , Nan Yu

Background modelling is one of the main challenges in particle physics data analysis. Commonly employed strategies include the use of simulated events of the background processes, and the fitting of parametric background models to the…

High Energy Physics - Experiment · Physics 2022-10-19 A. Chisholm , T. Neep , K. Nikolopoulos , R. Owen , E. Reynolds , J. Silva

Spectroscopy is an important tool for probing the properties of materials, chemicals and biological samples. We design a practical transmitter-receiver system that exploits entanglement to achieve a provable quantum advantage over all…

Quantum Physics · Physics 2020-11-03 Haowei Shi , Zheshen Zhang , Stefano Pirandola , Quntao Zhuang