Optics Commons^™

Rotation Of Two-Petal Laser Beams In The Near Field Of A Spiral Microaxicon, S. S. Stafeev, Liam O'Faolain, M. V. Kotlyar

Cappa Publications

Using a spiral microaxicon with the topological charge 2 and NA = 0.6 operating at a 532-nm wavelength and fabricated by electron-beam lithography, we experimentally demonstrate the rotation of a two-petal laser beam in the near field (several micrometers away from the axicon surface). The estimated rotation rate is 55 °/mm and linearly dependent on the on-axis distance, with the theoretical rotation rate being 53 °/mm. The experimentally measured rotation rate is found to be linear and coincident with the simulation results only on the on-axis segment from 1.5 to 3 mm. The experimentally measured rotation rate is 66 °/mm …

Assembling And Characterizing The Efficiency Of An Injection Locked Laser System For Cold Neutral Atom Optical Traps, Alexandra Papa Crawford

Physics

Creating a quantum computer requires a system of particles that can be well-controlled to achieve quantum operations. We need a large array of these particles – called qubits – with long coherence times, which can be initialized, operated on by single and two qubit gates, and read out. For neutral atoms, the qubit states are stable ground states that interact minimally with the environment, leading to long coherence times. Experimentally, the qubits are manipulated using carefully timed laser beam pulses with controlled frequency and intensity, but the outstanding issue for optically trapping cold atoms is finding a light pattern that …

Precision Spectroscopy Of Beryllium, Advik D. Vira

Theses, Dissertations, and Projects

We report on the calibration and absolute frequency results for the 2s2p1P1 state in neutral atomic beryllium-9. We start off with a discussion of the method used to calibrate the laser, which includes a detailed explanation of the basic physics involved, and then discuss the results for the lowest singlet state in neutral beryllium-9. We discuss a way to predict the spectra using optical Bloch equations and then present and analyze the experimental results. We found the absolute frequency for the 1P1 state to be 42565.4487(30) cm-1, which is in agreement with the current best theoretical estimateof42565.441(11)cm-1 [49]. Amoresophisticatedanalyticaltechniqueisproposed; however, …

Dispersive Quantum Interface With Atoms And Nanophotonic Waveguides, Xiaodong Qi

Physics & Astronomy ETDs

Strong coupling between atoms and light is critical for quantum information processing and precise sensing. A nanophotonic waveguide is a promising platform for realizing an atom-light interface that reaches the strong coupling regime. In this dissertation, we study the dispersive response theory of the nanowaveguide system as the means to create an entangling atom-light interface, with applications to quantum non-demolition (QND) measurement and spin squeezing.

We calculate the dyadic Green's function, which determines the scattering of light by atoms in the presence of a nanowaveguide, and thus the phase shift and polarization rotation induced on the guided light. The Green's …

Achieving A Stable Magneto-Optical Trap, Chasen S. Himeda

Honors Thesis

The utilization of the Magneto-Optical Trap (MOT) as a method for cooling and confining atoms is a recent development in the field of modern optical physics. Producing an effective MOT relies on a constant magnetic field throughout the trapping region and successful laser cooling, a technique used to achieve optical molasses by slowing particles using a three-dimensional intersection of laser beams. A successful MOT occurs when the trapped atoms slow down to approximately 30 cm/s at a temperature in the microkelvin range and is observable when a small bright orb of atoms is located in the center of the chamber. …

An Exploration Of The Optical Detection Of Ionizing Radiation Utilizing Modern Optics Technology, Sean D. Fournier, Adam Hecht, Cassiano De Oliveira, Jeffrey B. Martin, Richard K. Harrison, Charles Potter

Nuclear Engineering ETDs

Modern ultraviolet (UV) cameras, when combined with UV-transmitting lenses/filter arrangements, can be used to detect radiation dose in air. Ionizing radiation excites nitrogen molecules in ambient air, the resulting decay includes weak emission of ultraviolet photons. Previous work has proven this phenomenon is detectable using highly-sensitive electronically cooled cameras traditionally used in astronomy for low-background imaging. While the ability to detect the presence of radiation (i.e. qualitative measurement) has been demonstrated at Sandia National Laboratories, there are several challenges in correlating images to known dose-fields (quantitative measurement). These challenges include: a low signal to background ratio, interferences due to electronic …

Characterization Of Magnetic Thin Films Using The Magneto Optic Kerr Effect, Nicholas J. Savino

Student Scholar Showcase

Understanding magnetic properties of materials allows for advances in applications such as data storage. The Magneto-Optic Kerr Effect (MOKE) displays the reflective response a magnetic material has to a magnetic field. When polarized light reflects off of a magnetic material, the polarization orientation can change. The application of an external magnetic field can affect how much this polarization changes in a non-linear manner. Hysteresis loops are created when examining the relationship between intensity of the reflected light to the applied magnetic field provide information about magnetic properties of that material, such as the coercive field and field retention. Preliminary measurements …

Studies Of Light Generation With Four-Wave Mixing In A Cold Atomic Ensemble, Andrew Ferdinand

Physics & Astronomy ETDs

Correlated light generated from atomic ensembles can have a central role in prominent quantum information protocols, such as long-distance quantum communication. Here we present our studies on three topics involving the generation of correlated light with four-wave mixing (FWM) in a cold atomic ensemble for applications in quantum communications with high capacity. We experimentally investigate the generation of light with seeded FWM in cold cesium atoms and the time correlations of photon pairs generated with spontaneous FWM. We theoretically investigate the correlations in orbital angular momentum of photon pairs generated with spontaneous FWM for a range of experimental geometries. These …

Time-Resolved Electron (E,2E) Momentum Spectroscopy: Application To Laser-Driven Electron Population Transfer In Atoms, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

Owing to its ability to provide unique information on electron dynamics, time-resolved electron momentum spectroscopy (EMS) is used to study theoretically a laser-driven electronic motion in atoms. Specifically, a chirped laser pulse is used to adiabatically transfer the populations of lithium atoms from the ground state to the first excited state. During this process, impact ionization near the Bethe ridge by time-delayed ultrashort, high-energy electron pulses is used to image the instantaneous momentum density of this electronic population transfer. Simulations with 100 fs and 1 fs pulse durations demonstrate the capability of EMS to image the time-varying momentum density, including …

Analysis Of The Red And Green Optical Absorption Spectrum Of Gas Phase Ammonia, Nikolai F. Zobov, Phillip A. Coles, Roman I. Ovsyannikov, Aleksandra A. Kyuberis, Robert J. Hargreaves, Peter F. Bernath, Jonathan Tennyson, Sergei N. Yurchenko, Oleg L. Polyansky

Chemistry & Biochemistry Faculty Publications

Room temperature NH₃ absorption spectra recorded at the Kitt Peak National Solar Observatory in 1980 are analyzed. The spectra cover two regions in the visible: 15,200 - 15,700 cm^-1 and 17,950 - 18,250 cm^-1. These high overtone rotation-vibration spectra are analyzed using both combination differences and variational line lists. Two variational line lists were computed using the TROVE nuclear motion program: one is based on an ab initio potential energy surface (PES) while the other used a semi-empirical PES. Ab initio dipole moment surfaces are used in both cases. 95 energy levels with J = 1 …

Light Scattering From An Atomic Gas Under Conditions Of Quantum Degeneracy, V. M. Porozova, L. V. Gerasimov, M. D. Havey

Physics Faculty Publications

Elastic light scattering from a macroscopic atomic sample existing in the Bose-Einstein condensate phase reveals a unique physical configuration of interacting light and matter waves. However, the joint coherent dynamics of the optical excitation induced by an incident photon is influenced by the presence of incoherent scattering channels. For a sample of sufficient length the excitation transports as a polariton wave and the propagation Green's function obeys the scattering equation which we derive. The polariton dynamics could be tracked in the outgoing channel of the scattered photon as we show via numerical solution of the scattering equation for one-dimensional geometry. …

Studies Of Magnetically Induced Faraday Rotation By Polarized Helium-3 Atoms, Joshua Abney

Theses and Dissertations--Physics and Astronomy

Gyromagnetic Faraday rotation offers a new method to probe limits on properties of simple spin systems such as the possible magnetic moment of asymmetric dark matter or as a polarization monitor for polarized targets. Theoretical calculations predict the expected rotations of linearly polarized light due to the magnetization of spin-1/2 particles are close to or beyond the limit of what can currently be measured experimentally (10⁻⁹ rad). So far, this effect has not been verified. Nuclear spin polarized ³He provides an ideal test system due to its simple structure and ability to achieve high nuclear spin polarization via …

Novel Faraday Rotation Effects Observed In Ultra-Thin Iron Garnet Films, Brandon Blasiola

Dissertations, Master's Theses and Master's Reports

Recent work performed by A. Chakravarty and M. Levy showed experimentally a dramatic increase in the specific Faraday Rotation (FR) of the iron garnet Bi_0.8Lu_0.2Gd₂Fe₅O₁₂. A theoretical model, based purely on classical electrodynamics, attempting to explain this behavior was developed by colleagues in Russia that not only confirmed the asymptotic increase in the specific FR at sub-50nm film thicknesses but also suggested that the specific FR should exhibit significant fluctuations at sub-500 nm film thicknesses. The original data points were widespread with steps of 50 nm or more between data …

Theoretical Modeling And Design Of Photonic Structures In Zeolite Nanocomposites For Gas Sensing. Part Ii: Volume Gratings, Dervil Cody, Izabela Naydenova

Articles

The suitability of holographic structures fabricated in zeolite nanoparticle-polymer composite materials for gas sensing applications has been investigated. Theoretical modelling of the sensor response (i.e. change in hologram readout due to a change in refractive index modulation or thickness as a result of gas adsorption) of different sensor designs was carried out using Raman-Nath theory and Kogelnik’s Coupled Wave Theory. The influence of a range of parameters on the sensitivity of holographically-recorded surface and volume photonic structures has been studied, namely hologram geometry, hologram thickness and spatial frequency, reconstruction wavelength, and zeolite nanoparticle refractive index. From this, the optimum fabrication …

Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies, Amanda Schilling

Graduate Theses and Dissertations

I have investigated the energy output of active galactic nuclei (AGN) in order to understand how these objects evolve and the impact they may have on host galaxies. First, I looked at a sample of 96 AGN at redshifts $z \sim 2, 3,$ and $4$ which have imaging and thus luminosity measurements in the $griz$ and $JHK$ observed wavebands. For these galaxies, I have co-epochal data across those bands which accounted for variability in AGN luminosity. I used the luminosity measurements in the five bands to construct spectral energy distributions (SED) in the emitted optical-UV bands for each AGN. I …

Raman Spectroscopy Of Oxygen Evolution Catalysts And Psii Manganese Model Compounds, Sergei Shmakov, Daniel A. Hartzler, Alireza Karbakhsh Ravari, Yulia Pushkar

The Summer Undergraduate Research Fellowship (SURF) Symposium

Photosynthesis is the basis of life on earth, and oxygen evolution catalysts are key components of this complicated, yet not fully understood process. Photosystem II, a large membrane bound pigment-protein complex, is the key system that facilitates oxygenic photosynthesis via the oxygen evolving complex (a natural oxygen evolving catalyst). It is a key component in oxygen producing catalysts, which can be used in fields such as energy production and biomimetic catalysts. The oxygen evolution cycle, or Kok cycle going within it is still not studied completely. In this project, we were studying the vibrational (and structural) state of a Manganese …

Optimizing An Electron's Path To Ionization Using A Genetic Algorithm, Jason Bennett, Kevin Choice

Physics and Astronomy Summer Fellows

A Rydberg atom is an atom with a highly excited and weakly bound valence electron. A widespread method of studying quantum mechanics with Rydberg atoms is to ionize the electron and measure its arrival time. We use a Genetic Algorithm (GA) to control the electron's path to ionization. The Rydberg electron's energy levels are strongly shifted by the presence of an electric field. The energy levels shift and curve, but never cross. At an avoided crossing the electron can jump from one level to the next. By engineering the electric field's time dependence, we thereby control the path to ionization. …

Quantum Optical Interferometry And Quantum State Engineering, Richard J. Birrittella Jr

Dissertations, Theses, and Capstone Projects

We highlight some of our research done in the fields of quantum optical interferometry and quantum state engineering. We discuss the body of work for which our research is predicated, as well as discuss some of the fundamental tenants of the theory of phase estimation. We do this in the context of quantum optical interferometry where our primary interest lies in the calculation of the quantum Fisher information as it has been shown that the minimum phase uncertainty obtained, the quantum Cramer-Rao bound, is saturated by parity-based detection methods. We go on to show that the phase uncertainty one obtains …

Time-Resolved Thz Conductivity Of An Intermediate Band Semiconductor, Elliot Weiss

Macalester Journal of Physics and Astronomy

Intermediate band materials have promising applications as affordable, highly efficient solar materials. However, intermediate band solar cells exhibit low efficiency to date. Carrier recombination is a critical process that limits efficiency. If electrons relax to the valence band before they can be collected, their energy is lost. To help understand the recombination dynamics and physical properties of intermediate band semiconductors, we obtain time-resolved THz conductivity measurements of the intermediate band semiconductor, GaPAsN, at various temperatures. From our results, we build a model that provides insight to the recombination dynamics of GaPAsN.

Conductivity Measurements Of A Thermoelectric Nanomaterial Through Thz Spectroscopy, Michaela S. Koller, James Heyman, Gunnar Footh

Macalester Journal of Physics and Astronomy

In today’s society there is a great demand on energy output—in the United States alone we rely heavily on non-renewable energy sources. Thermoelectric materials may be able to be used to create more efficient energy systems or recover wasted heat from inefficient technologies. This paper focuses on the conductivity of a new thermoelectric material that incorporates copper into a tellurium nanowire PEDOT:PSS material. The addition of copper seems to increase the conductivity of the material, although the exact relationship between the percentage of copper to tellurium and its affect on the conductivity is uncertain from the results.

Studies In Mesoscopics And Quantum Microscopies, Zhenghao Ding, Gabriel C. Spalding

Honors Projects

This thesis begins with a foundational section on quantum optics. The single-photon detectors used in the first chapter were obtained through the Advanced Laboratory Physics Association (ALPhA), which brokered reduced cost for educational use, and the aim of the single-photon work presented in Chapter 1 is to develop modules for use in Illinois Wesleyan's instructional labs beyond the first year of university. Along with the American Association of Physics Teachers, ALPhA encourages capstone-level work, such as Chapter 1 of this honors thesis, which is explicitly designed to play the role of passing on, to a next generation of physics majors, …

Index Of Refraction From The Near-Ultraviolet To The Near-Infrared From A Single Crystal Microwave-Assisted Cvd Diamond, Giorgio Turri, Scott Webster, Ying Chen, Benjamin Wickham, Andrew Bennett, Michael Bass

Publications

The refractive index of a type IIa CVD-grown single-crystal diamond was measured by ellipsometry from the near ultraviolet to the near infrared region of the spectrum. As a consequence, a one term Sellmeier Equation with coefficents of B-1 = 4.658 and C-1 = 112.5 for the refractive index of diamond, for the wavelength range from 300 to 1650 nm, was derived that is only as accurate as the input data, +/- 0.002. The experimental results in this paper between 800 and 1650 nm are new, adding to the values available in the literature.

Development Of A Compact Broadband Optical Parametric Oscillator For Ultra-Sensitive Molecular Detection, Sean O. Crystal

Honors Undergraduate Theses

Every gas molecule has a unique absorption spectrum that can be captured using optical spectroscopy to identify an unknown sample's composition. Frequency combs systems can provide an extremely broad mid-infrared spectrum that is very useful for molecular detection. A degenerate optical parametric oscillator (OPO) was built to generate the down-converted and shifted frequency comb spectrum. This system utilizes an ultra-short pulse 1.56µm pump laser and a never before used orientation patterned gallium-phosphide crystal. Periodically polled lithium niobate (PPLN), Gallium Arsenide (GaAs) and Gallium Phosphide are all crystals used to accomplish this task. GaP, in comparison to PPLN, has (i) a …

Development And Characterisation Of A Bath-Based Vertical Blackbody Cavity Calibration Source For The Range −30 °C To 150 °C, Sam Boles, Igor Pušnik, Dubhaltach Mac Lochlainn, David Fleming, Izabela Naydenova, Suzanne Martin

Articles

Industrial use of Radiation Thermometers (RTs) is becoming increasingly common due to the perceived advantages and wide market availability. Blackbody Cavity Radiation Sources (BCRSs) are typically used for calibration of these instruments, and these cavities are oriented horizontally in most cases. For BCRSs based in thermal baths, this necessitates the use of custom-built baths with side openings. This paper presents a unique design of vertical bath-based BCRS that may be immersed in conventional calibration baths without modifications to the baths. The method, results, and analysis of an international comparison comparing this vertical BCRS, standard horizontal BCRSs, and a previous iteration …

Cavity Ringdown Spectroscopy In Nitrogen/Oxygen Mixtures In The Presence Of Alpha Radiation, Sidney John Gautrau

Master's Theses

This research was part of an effort to experimentally validate computational models under development for radiation-induced atmospheric effects. Cavity Ringdown Spectroscopy (CRDS) was used to measure the concentration of chemical products generated as a result of radiation interactions in a controlled atmosphere. Experiments were conducted in a vacuum chamber interfaced with a gas introduction system that controlled the initial atmospheric composition. A quadrupole mass spectrometer and tunable dye laser were integrated to confirm initial atmospheric composition, and provide wavelength flexibility for detecting a variety of chemical products generated by radiation interactions. CRDS measurements were made for ozone production resulting from …

Control Of Spontanous Emission From Quantum Emitters Using Hyperbolic Metamaterial Substrates, Tal Galfsky

Dissertations, Theses, and Capstone Projects

Hyperbolic metamaterials (HMMs) are so named for possessing a hyperboloid-shaped dispersion which gives rise to a large photonic density of states. Quantum emitters placed inside or in the near-field of a HMM have been shown to exhibit strong enhancement of spontaneous emission due to the increase in available states. This thesis focuses on enhancing spontaneous emission of quantum emitters in optical frequencies by utilizing multilayered metal/dielectric composites that form these highly anisotropic metamaterials. In conjunction with the enhanced decay rate we experimentally demonstrate two methods for shaping and directing radiation trapped in the HMM into free space by employing a …

Photonicstd-2d: Modeling Light Scattering In Periodic Multilayer Photonic Structures, Alexey Bondarev, Shaimaa Azzam, Zhaxylyk Kudyshev, Alexander V. Kildishev

The Summer Undergraduate Research Fellowship (SURF) Symposium

Efficient modeling of electromagnetic processes in optical and plasmonic metamaterials is important for enabling new and exciting ways to manipulate light for advanced applications. In this work, we put together a tool for numerical simulation of propagation of normally incident light through a nanostructured multilayer composite material. The user builds a unit cell of a given material layer-by-layer starting from a substrate up to a superstrate, splitting each layer further into segments. The segments are defined by width and material -- dielectric, metal or active medium. Simulations are performed with the finite difference time domain (FDTD) method. A database of …

Emergence Of Collective Light Scattering In Atomic 87Rb Samples, Kasie Jean Kemp

Physics Theses & Dissertations

Over the past half century, atomic ensembles have been used to create sensors, clocks, and quantum information systems. As these devices become more compact, and as the number of atoms increases to improve the sensitivity for detection, the atomic samples are increasing in density and optical depth. As such, the spectroscopic properties of the atomic media are modified due to interactions among the particles in the ensemble. We report investigation of near-resonance light scattering from a cold atomic sample of 87Rb. Initially prepared in a magneto-optical trap, the atoms are loaded into a far-off-resonance optical dipole trap (FORT) in which …

Spontaneous Parametric Down Conversion Of Photons Through Β-Barium Borate, Luke Horowitz

Physics

An apparatus for detecting pairs of entangled 405nm photons that have undergone Spontaneous Parametric Down Conversion through β-Barium Borate is described. By using avalanche photo-diodes to detect the low-intensity converted beam and a coincidence module to register coincident photons, it is possible to create an apparatus than can be used to perform quantum information experiments under a budget appropriate for an undergraduate physics lab.

Diffractive Imaging Of A Rotational Wavepacket In Nitrogen Molecules With Femtosecond Megaelectronvolt Electron Pulses, Jie Yang, Markus Guehr, Theodore Vecchione, Matthew S. Robinson, Renkai Li, Nick Hartmann, Xiaozhe Shen, Ryan Coffee, Jeff Corbett, Alan Fry, Kelly Gaffney, Tais Gorkhover, Carsten Hast, Keith Jobe, Igor Makasyuk, Alexander Reid, Joseph Robinson, Sharon Vetter, Fenglin Wang, Stephen Weathersby, Charles Yoneda, Martin Centurion, Xijie Wang

Martin Centurion Publications

This work is licensed under a Creative Commons Attribution 4.0 International License.