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- Holography (6)
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- Coherence (Optics) (2)
- HOE (2)
- Acoustic levitation (1)
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- Adaptive photonics (1)
- Adhesion (1)
- Amblyopia (1)
- Analog holographic wavefront sensor (1)
- Analogues (1)
- Apex angles (1)
- Atomic force microscopy (1)
- Attenuation coefficient (1)
- Bacteria (1)
- Bangerter foils (1)
- Bayfol (1)
- Bidirectional reflectance distribution functions (1)
- Blades (1)
- Bragg selectivity (1)
- Cantilever (1)
- Concept Connectivity (1)
- Diffraction gratings (1)
- Diffractive element (1)
- Diffration (1)
- Diffusers (1)
- Digital logic (1)
- Electro-optical and infrared (EO/IR) systems (1)
- Electrode Kinetics (1)
- Electrolyte Stability (1)
- Elementary geometry (1)
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- Conference Papers (6)
- Faculty Publications (6)
- Articles (3)
- AFIT Patents (2)
- Engineering Faculty Articles and Research (2)
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- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (1)
- Department of Physics and Astronomy: Dissertations, Theses, and Student Research (1)
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- Physics, Astronomy and Geophysics Honors Papers (1)
Articles 1 - 24 of 24
Full-Text Articles in Physics
Development Of An Optical Test Bed For The Fabrication And Characterisation Of An Analog Holographic Wavefront Sensor, Emma Branigan, Andreas Zepp, Suzanne Martin, Matthew Sheehan, Szymon Gladysz, Kevin Murphy
Development Of An Optical Test Bed For The Fabrication And Characterisation Of An Analog Holographic Wavefront Sensor, Emma Branigan, Andreas Zepp, Suzanne Martin, Matthew Sheehan, Szymon Gladysz, Kevin Murphy
Conference Papers
A new holographic recording setup has been developed for the fabrication of single- and multi-mode photopolymer-based analog holographic wavefront sensors. A second setup has been built and used to characterise the sensor at several wavelengths.
Acoustically Levitated Whispering-Gallery Mode Microlasers, H. M. Reynoso-De La Cruz, E. D. Hernández-Campos, E. Ortiz-Ricardo, A. Martínez-Borquez, I. Rosas-Román, V. Contreras, G. Ramos-Ortiz, B. Mendoza-Santoyo, Cecilia Zurita-Lopez, R. Castro-Beltrán
Acoustically Levitated Whispering-Gallery Mode Microlasers, H. M. Reynoso-De La Cruz, E. D. Hernández-Campos, E. Ortiz-Ricardo, A. Martínez-Borquez, I. Rosas-Román, V. Contreras, G. Ramos-Ortiz, B. Mendoza-Santoyo, Cecilia Zurita-Lopez, R. Castro-Beltrán
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Acoustic levitation has become a crucial technique for contactless manipulation in several fields, particularly in biological applications. However, its application in the photonics field remains largely unexplored. In this study, we implement an affordable and innovative phased-array levitator that enables stable trapping in the air of micrometer dye-doped droplets, thereby enabling the creation of microlasers. For the first time, this paper presents a detailed performance of the levitated microlaser cavity, supported by theoretical analysis concerning the hybrid technology based on the combination of whispering-gallery modes and acoustic fields. The pressure field distribution inside the acoustic cavity is numerically solved and …
System-Level Noise Performance Of Coherent Imaging Systems, Derek J. Burrell, Joshua H. Follansbee, Mark F. Spencer, Ronald G. Driggers
System-Level Noise Performance Of Coherent Imaging Systems, Derek J. Burrell, Joshua H. Follansbee, Mark F. Spencer, Ronald G. Driggers
Faculty Publications
We provide an in-depth analysis of noise considerations in coherent imaging, accounting for speckle and scintillation in addition to “conventional” image noise. Specifically, we formulate closed-form expressions for total effective noise in the presence of speckle only, scintillation only, and speckle combined with scintillation. We find analytically that photon shot noise is uncorrelated with both speckle and weak-to-moderate scintillation, despite their shared dependence on the mean signal. Furthermore, unmitigated speckle and scintillation noise tends to dominate coherent-imaging performance due to a squared mean-signal dependence. Strong coupling occurs between speckle and scintillation when both are present, and we characterize this behavior …
Active-Illumination Extension To The Priest And Meier Pbrdf, Mark F. Spencer, Milo W. Hyde Iv, Santasri R. Bose-Pillai, Michael A. Marciniak
Active-Illumination Extension To The Priest And Meier Pbrdf, Mark F. Spencer, Milo W. Hyde Iv, Santasri R. Bose-Pillai, Michael A. Marciniak
Faculty Publications
This paper develops a 3D vector solution for the scattering of partially coherent laser-beam illumination from statistically rough surfaces. Such a solution enables a rigorous comparison to the well-known Priest and Meier polarimetric bidirectional reflectance distribution function (pBRDF) [Opt Eng 41(5),988 (2002).]. Overall, the comparison shows excellent agreement for the normalized spectral density and the degree of polarization. Based on this agreement, the 3D vector solution also enables an extension to the Priest and Meier pBRDF that accounts for the effects of active illumination. In particular, the 3D vector solution enables the development of a closed-form expression for the spectral …
Propagation Of Spatiotemporal Optical Vortex Beams In Linear, Second-Order Dispersive Media, Milo W. Hyde Iv, Miguel A. Porras
Propagation Of Spatiotemporal Optical Vortex Beams In Linear, Second-Order Dispersive Media, Milo W. Hyde Iv, Miguel A. Porras
Faculty Publications
In this paper, we study the behaviors of spatiotemporal optical vortex (STOV) beams propagating in linear dispersive media. Starting with the Fresnel diffraction integral, we derive a closed-form expression for the STOV field at any propagation distance z in a general second-order dispersive medium. We compare our general result to special cases published in the literature and examine the characteristics of higher-order STOV beams propagating in dispersive materials by varying parameters of the medium and source-plane STOV field. We validate our analysis by comparing theoretical predictions to numerical computations of a higher-order STOV beam propagating through fused silica, where we …
Wave Optics Approach To Solar Cell Brdf Modeling With Experimental Results, Madilynn Compean, Todd V. Small, Milo W. Hyde Iv, Michael Marciniak
Wave Optics Approach To Solar Cell Brdf Modeling With Experimental Results, Madilynn Compean, Todd V. Small, Milo W. Hyde Iv, Michael Marciniak
Faculty Publications
Light curve analysis is often used to discern information about satellites in geosynchronous orbits. Solar panels, comprising a large part of the satellite’s body, contribute significantly to these light curves. Historically, theoretical bidirectional reflectance distribution functions (BRDFs) have failed to capture key features in the scattered light from solar panels. In recently published work, a new solar cell BRDF was developed by combining specular microfacet and “two-slit” diffraction terms to capture specular and periodic/array scattering, respectively. This BRDF was experimentally motivated and predicted many features of the solar cell scattered irradiance. However, the experiments that informed the BRDF were limited …
Adaptive Plasmonic Metasurfaces For Radiative Cooling And Passive Thermoregulation, Azadeh Didari-Bader, Nooshin M. Estakhri, Nasim Mohammadi Estrakhri
Adaptive Plasmonic Metasurfaces For Radiative Cooling And Passive Thermoregulation, Azadeh Didari-Bader, Nooshin M. Estakhri, Nasim Mohammadi Estrakhri
Engineering Faculty Articles and Research
In this work, we investigate a class of planar photonic structures operating as passive thermoregulators. The radiative cooling process is adjusted through the incorporation of a phase change material (Vanadium Dioxide, VO2) in conjunction with a layer of transparent conductive oxide (Aluminum-doped Zinc Oxide, AZO). VO2 is known to undergo a phase transition from the “dielectric” phase to the “plasmonic” or “metallic” phase at a critical temperature close to 68°C. In addition, AZO shows plasmonic properties at the long-wave infrared spectrum, which, combined with VO2, provides a rich platform to achieve low reflections across the …
Optical Characterisation Of Holographic Diffusers And Bangerter Foils For Treatment Of Amblyopia, Matthew Hellis, Suzanne Martin, Matthew Sheehan, Kevin Murphy
Optical Characterisation Of Holographic Diffusers And Bangerter Foils For Treatment Of Amblyopia, Matthew Hellis, Suzanne Martin, Matthew Sheehan, Kevin Murphy
Articles
Amblyopia is a significant issue for children worldwide, and current treatment methods have drawbacks that can hinder treatment effectiveness and/or patient experience. This study proposes a new treatment method using holographic diffusers while also comparing their optical characteristics to a current treatment method (Bangerter foils). Holographic diffusers were developed by optically patterning thin polymer layers on a micron scale. Two compositions of photopolymer (acrylamide and diacetone acrylamide based) are analysed herein. Characterisation shows that holographic diffusers of either composition can achieve a wide range of on-axis intensity reductions, allowing for precise and customisable treatment levels by altering recording exposure time …
Modelling Hoe Performance With An Extended Source; Experimental Investigation Using Misaligned Point Sources, Jorge Lasarte, Kevin Murphy, Izabela Naydenova, Jesús Atencia, Mª Victoria Collados, Suzanne Martin
Modelling Hoe Performance With An Extended Source; Experimental Investigation Using Misaligned Point Sources, Jorge Lasarte, Kevin Murphy, Izabela Naydenova, Jesús Atencia, Mª Victoria Collados, Suzanne Martin
Conference Papers
Holographic Optical Elements (HOEs) have the potential to enable more compact, versatile and lightweight optical designs, but many challenges remain. Volume HOE’s have the advantage of high diffraction efficiency but they present both chromatic selectivity and chromatic dispersion which impact on their use with wide spectrum light sources. Single-colour LED sources have a narrow spectrum that reduces these issues and this makes them better suited for use with volume HOEs. However, the LED source size must be taken into consideration for compact volume HOE-LED systems. To investigate the design limits for compact HOE-LED systems, a theoretical and experimental study was …
Method Of Evanescently Coupling Whispering Gallery Mode Optical Resonators Using Liquids, Hengky Chandrahalim, Kyle T. Bodily
Method Of Evanescently Coupling Whispering Gallery Mode Optical Resonators Using Liquids, Hengky Chandrahalim, Kyle T. Bodily
AFIT Patents
The present invention relates to evanescently coupling whispering gallery mode optical resonators having a liquid coupling as well as methods of making and using same. The aforementioned evanescently coupling whispering gallery mode optical resonators having a liquid couplings provide increased tunability and sensing selectivity over current same. The aforementioned. Applicants’ method of making evanescent-wave coupled optical resonators can be achieved while having coupling gap dimensions that can be fabricated using standard photolithography. Thus economic, rapid, and mass production of coupled WGM resonators-based lasers, sensors, and signal processors for a broad range of applications can be realized.
Optical Fiber Tip Micro Anemometer, Jeremiah C. Williams, Hengky Chandrahalim
Optical Fiber Tip Micro Anemometer, Jeremiah C. Williams, Hengky Chandrahalim
AFIT Patents
A passive microscopic flow sensor includes a three-dimensional microscopic optical structure formed on a cleaved tip of an optical fiber. The three-dimensional microscopic optical structure includes a post attached off-center to and extending longitudinally from the cleaved tip of the optical fiber. A rotor of the three-dimensional microscopic optical structure is received for rotation on the post. The rotor has more than one blade. Each blade has a reflective undersurface that reflects a light signal back through the optical fiber when center aligned with the optical fiber, the blades of the rotor shaped to rotate at a rate related to …
Diffractive Imaging Of Laser Induced Molecular Reactions With Kiloelectron-Volt Ultrafast Electron Diffraction, Yanwei Xiong
Diffractive Imaging Of Laser Induced Molecular Reactions With Kiloelectron-Volt Ultrafast Electron Diffraction, Yanwei Xiong
Department of Physics and Astronomy: Dissertations, Theses, and Student Research
Capturing the structural changes during a molecular reaction with ultrafast electron diffraction (UED) requires a high spatiotemporal resolution and sufficiently high signal-to-noise to record the signals with high fidelity. In this dissertation, I have focused on the development of a tabletop gas phase keV-UED setup with a femtosecond temporal resolution. A DC electron gun was employed to generate electron pulses with a high repetition rate of 5 kHz. The space charge effect in the electron pulse was ameliorated by compressing the 90 keV electron pulse longitudinally with a time varying electric field in an RF cavity. The velocity mismatch between …
Utilizing Inverse Design To Create Plasmonic Waveguide Devices, Michael Efseaff, Kyle Wynne, Mark C. Harrison
Utilizing Inverse Design To Create Plasmonic Waveguide Devices, Michael Efseaff, Kyle Wynne, Mark C. Harrison
Engineering Faculty Articles and Research
In modern communications networks, data is transmitted over long distances using optical fibers. At nodes in the network, the data is converted to an electrical signal to be processed, and then converted back into an optical signal to be sent over fiber optics. This process results in higher power consumption and adds to transmission time. However, by processing the data optically, we can begin to alleviate these issues and surpass systems which rely on electronics. One promising approach for this is plasmonic devices. Plasmonic waveguide devices have smaller footprints than silicon photonics for more compact photonic integrated circuits, although they …
Numerical Simulation Of Steady-State Thermal Blooming With Natural Convection, Jeremiah S. Lane, Justin Cook, Martin Richardson, Benjamin F. Akers
Numerical Simulation Of Steady-State Thermal Blooming With Natural Convection, Jeremiah S. Lane, Justin Cook, Martin Richardson, Benjamin F. Akers
Faculty Publications
This work investigates steady-state thermal blooming of a high-energy laser in the presence of laser-driven convection. While thermal blooming has historically been simulated with prescribed fluid velocities, the model introduced here solves for the fluid dynamics along the propagation path using a Boussinesq approximation to the incompressible Navier–Stokes equations. The resultant temperature fluctuations were coupled to refractive index fluctuations, and the beam propagation was modeled using the paraxial wave equation. Fixed-point methods were used to solve the fluid equations as well as to couple the beam propagation to the steady-state flow. The simulated results are discussed relative to recent experimental …
Development Of Holographic Optical Elements For Use In Wound Monitoring, Pamela Stoeva, Tatsiana Mikulchyk, Brian Rogers, M. Oubaha, Suzanne Martin, Dervil Cody, M.A. Ferrara, G. Coppola, Izabela Naydenova
Development Of Holographic Optical Elements For Use In Wound Monitoring, Pamela Stoeva, Tatsiana Mikulchyk, Brian Rogers, M. Oubaha, Suzanne Martin, Dervil Cody, M.A. Ferrara, G. Coppola, Izabela Naydenova
Conference Papers
Wounds that fail to heal impact the quality of life of 2.5 % of the total population. The costs of chronic wound care will reach $15–22 billion by 2024. These alarming statistics reveal the financial strain for both the medical industry and society. A solution can be found in compact and accessible sensors that offer real-time analysis of the wound site, facilitating continuous monitoring and immediate treatment, if required. Benefits of these sensors include reduction of cost and can extend the reach of healthcare to remote areas. The progression of a wound site can be closely monitored with holographic optical …
Fabrication And Characterisation Of Large Area, Uniform And Controllable Surface Relief Patterns In Photopolymer Material, Owen Kearney, Izabela Naydenova
Fabrication And Characterisation Of Large Area, Uniform And Controllable Surface Relief Patterns In Photopolymer Material, Owen Kearney, Izabela Naydenova
Conference Papers
As the risk of antibiotic resistant pathogens increases, development of convenient point of care devices is essential. Such devices would help avoid infection – ensure cleanliness of environments and assist in bacteria analysis. The ultimate aim of the research presented here is to develop a compact, cost effective, easy to use optical device which is capable of detecting and quantifying bacteria in an aqueous sample. The surface relief patterns have a dual role, they provide a diffracted light signal, and control the adhesion of the bacteria to the surface. The strength of the diffracted signal is expected to provide a …
Design, Construction, And Stabilization Of An Adjustable Repetition Rate Frequency Comb For Precision Spectroscopy, Matthew Carter
Design, Construction, And Stabilization Of An Adjustable Repetition Rate Frequency Comb For Precision Spectroscopy, Matthew Carter
Physics, Astronomy and Geophysics Honors Papers
Optical frequency combs have numerous applications across the sciences. One of the most powerful applications is in molecular spectroscopy, which takes advantage of both the coherence of lasers and combs’ inherent broad bandwidth. One well-established design is the erbium fiber comb, which is popular due to its low cost and relative ease of construction. I have modified the traditional all-fiber design by introducing an adjustable free-space section which allows for adjustments to the path length, and thus the comb’s repetition rate. This low-cost addition allows for repetition rate matching, a necessity for dual-comb spectroscopy, and active repetition rate stabilization, which …
The Development Of Optomechanical Sensors—Integrating Diffractive Optical Structures For Enhanced Sensitivity, Faolan Radford Mcgovern, Aleksandra Hernik, Catherine M. Grogan, George Amarandei, Izabela Naydenova
The Development Of Optomechanical Sensors—Integrating Diffractive Optical Structures For Enhanced Sensitivity, Faolan Radford Mcgovern, Aleksandra Hernik, Catherine M. Grogan, George Amarandei, Izabela Naydenova
Conference Papers
The term optomechanical sensors describes devices based on coupling the optical and mechanical sensing principles. The presence of a target analyte leads to a mechanical change, which, in turn, determines an alteration in the light propagation. Having higher sensitivity in comparison with the individual technologies upon which they are based, the optomechanical devices are used in biosensing, humidity, temperature, and gases detection. This perspective focuses on a particular class, namely on devices based on diffractive optical structures (DOS). Many configurations have been developed, including cantilever- and MEMS-type devices, fiber Bragg grating sensors, and cavity optomechanical sensing devices. These state-of-the-art sensors …
Color-Changing Reflection Hologram For Quality Assurance Of Therapeutic Ultrasound Systems, Tatsiana Mikulchyk, John Walsh, Jacinta Browne, Izabela Naydenova, Dervil Cody
Color-Changing Reflection Hologram For Quality Assurance Of Therapeutic Ultrasound Systems, Tatsiana Mikulchyk, John Walsh, Jacinta Browne, Izabela Naydenova, Dervil Cody
Articles
The acoustic output of clinical therapeutic ultrasound equipment requires regular quality assurance (QA) testing to ensure the safety and efficacy of the treatment and that any potentially harmful deviations from the expected output power density are detected as soon as possible. A hologram, consisting of a reflection grating fabricated in an acrylate photopolymer film, has been developed to produce an immediate, visible, and permanent change in the color of the reconstructed hologram from red to green in response to incident ultrasound energy. The influence of the therapeutic ultrasound insonation parameters (exposure time, ultrasound power density, and proximity to the point …
Design And Fabrication Of Volume Holographic Optical Couplers For A Range Of Non-Normal Incidence Angles, Dipanjan Chakraborty, Rosen Georgiev, Sinead Aspell, Izabela Naydenova, Suzanne Martin
Design And Fabrication Of Volume Holographic Optical Couplers For A Range Of Non-Normal Incidence Angles, Dipanjan Chakraborty, Rosen Georgiev, Sinead Aspell, Izabela Naydenova, Suzanne Martin
Conference Papers
A theoretical model has previously been developed to calculate the holographic recording beam angles required in air (at any recording wavelength) to produce a Volume Holographic Optical Element (VHOE) for operation as a coupler for different input and output angles. In this paper, the experimental study is extended to further validate the VHOE coupler design and fabrication approach for additional incident beam angles, comparing -40° -45° and -50° (in air). The output angle for each VHOE is +45° within the medium and the coupler operational wavelength is 633nm. Holographic recording in Bayfol HX 200 photopolymer at 532nm is used to …
Review-Electrode Kinetics And Electrolyte Stability In Vanadium Flow Batteries, Andrea Bourke, Daniela Oboroceanu, Nathan Quill, Catherine Lenihan, Maria Alhajji Safi Maria Alhajji Safi, Mallory A. Miller, Robert F. Savinell, Jesse S. Wainright, Varsha Sasikumarsp, Maria Rybalchenko, Pupak Amini, Niall Dalton, Robert P. Lynch, D. Noel Buckley
Review-Electrode Kinetics And Electrolyte Stability In Vanadium Flow Batteries, Andrea Bourke, Daniela Oboroceanu, Nathan Quill, Catherine Lenihan, Maria Alhajji Safi Maria Alhajji Safi, Mallory A. Miller, Robert F. Savinell, Jesse S. Wainright, Varsha Sasikumarsp, Maria Rybalchenko, Pupak Amini, Niall Dalton, Robert P. Lynch, D. Noel Buckley
Articles
Two aspects of vanadium flow batteries are reviewed: electrochemical kinetics on carbon electrodes and positive electrolyte stability. There is poor agreement between reported values of kinetic parameters; however, most authors report that kinetic rates are faster for VIV/VV than for VII/VIII. Cycling the electrode potential increases the rates of both reactions initially due to roughening but when no further roughening is observed, the VII/VIII and VIV/VV reactions are affected oppositely by the pretreatment potential. Anodic pretreatment activates the electrode for the VII/VIII reaction, and deactivates it for VIV/VV. Three states of the carbon surface are suggested: reduced and oxidized states …
Concept Connectivity: An Educational And Research Framework For Scientific Learning In Optics, Photonics, And Electronic Education, Benjamin Dingel, John Gabriel C. Rivera, Francesca De Guzman Palabrica, Clint Dominic Bennett
Concept Connectivity: An Educational And Research Framework For Scientific Learning In Optics, Photonics, And Electronic Education, Benjamin Dingel, John Gabriel C. Rivera, Francesca De Guzman Palabrica, Clint Dominic Bennett
Physics Faculty Publications
We present a novel framework referred to as Concept Connectivity that aids in educating and engaging students by presenting the topic of the Special Theory of Relativity (STR) in a coherent and unified manner. It uses different analogue implementations of the STR coming from seemingly distinct fields of study such as (i) Optics, (ii) Photonics, and (iii) Electronics to connect not only to the concepts of the STR but to the various concepts from these different fields. In these analogue implementations, the fundamental characteristics of the different STR phenomena can be mimicked in many different ways. Concept Connectivity has two …
Another Angle On Perspective, John Adam
Another Angle On Perspective, John Adam
Mathematics & Statistics Faculty Publications
No abstract provided.
The Behavior Of Partially Coherent Twisted Space-Time Beams In Atmospheric Turbulence, Milo W. Hyde Iv
The Behavior Of Partially Coherent Twisted Space-Time Beams In Atmospheric Turbulence, Milo W. Hyde Iv
Faculty Publications
We study how atmospheric turbulence affects twisted space-time beams, which are non-stationary random optical fields whose space and time dimensions are coupled with a stochastic twist. Applying the extended Huygens–Fresnel principle, we derive the mutual coherence function of a twisted space-time beam after propagating a distance z through atmospheric turbulence of arbitrary strength. We specialize the result to derive the ensemble-averaged irradiance and discuss how turbulence affects the beam’s spatial size, pulse width, and space-time twist. Lastly, we generate, in simulation, twisted space-time beam field realizations and propagate them through atmospheric phase screens to validate our analysis.