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Full-Text Articles in Optics

Avoiding Loopholes With Hybrid Bell-Leggett-Garg Inequalities, Justin Dressel, Alexander N. Korotkov Jan 2014

Avoiding Loopholes With Hybrid Bell-Leggett-Garg Inequalities, Justin Dressel, Alexander N. Korotkov

Mathematics, Physics, and Computer Science Faculty Articles and Research

By combining the postulates of macrorealism with Bell locality, we derive a qualitatively different hybrid inequality that avoids two loopholes that commonly appear in Leggett-Garg and Bell inequalities. First, locally invasive measurements can be used, which avoids the “clumsiness” Leggett-Garg inequality loophole. Second, a single experimental ensemble with fixed analyzer settings is sampled, which avoids the “disjoint sampling” Bell inequality loophole. The derived hybrid inequality has the same form as the Clauser-Horne-Shimony-Holt Bell inequality; however, its quantum violation intriguingly requires weak measurements. A realistic explanation of an observed violation requires either the failure of Bell locality or a preparation conspiracy …


Improving Einstein–Podolsky–Rosen Steering Inequalities With State Information, James Schneeloch, Curtis J. Broadbent, John C. Howell Jan 2014

Improving Einstein–Podolsky–Rosen Steering Inequalities With State Information, James Schneeloch, Curtis J. Broadbent, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We discuss the relationship between entropic Einstein–Podolsky–Rosen (EPR)-steering inequalities and their underlying uncertainty relations along with the hypothesis that improved uncertainty relations lead to tighter EPR-steering inequalities. In particular, we discuss how using information about the state of a quantum system affects oneʼs ability to witness EPR-steering. As an example, we consider the recent improvement to the entropic uncertainty relation between pairs of discrete observables (Berta et al., 2010 [10]). By considering the assumptions that enter into the development of a steering inequality, we derive correct steering inequalities from these improved uncertainty relations and find that they are identical to …


Photon Counting Compressive Depth Mapping, Gregory A. Howland, Daniel J. Lum, Matthew R. Ware, John C. Howell Sep 2013

Photon Counting Compressive Depth Mapping, Gregory A. Howland, Daniel J. Lum, Matthew R. Ware, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We demonstrate a compressed sensing, photon counting lidar system based on the single-pixel camera. Our technique recovers both depth and intensity maps from a single under-sampled set of incoherent, linear projections of a scene of interest at ultra-low light levels around 0.5 picowatts. Only two-dimensional reconstructions are required to image a three-dimensional scene. We demonstrate intensity imaging and depth mapping at 256 × 256 pixel transverse resolution with acquisition times as short as 3 seconds. We also show novelty filtering, reconstructing only the difference between two instances of a scene. Finally, we acquire 32 × 32 pixel real-time video for …


Technical Advantages For Weak-Value Amplification: When Less Is More, Andrew N. Jordan, Julián Martínez-Rincón, John C. Howell Sep 2013

Technical Advantages For Weak-Value Amplification: When Less Is More, Andrew N. Jordan, Julián Martínez-Rincón, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

The technical merits of weak-value-amplification techniques are analyzed. We consider models of several different types of technical noise in an optical context and show that weak-value-amplification techniques (which only use a small fraction of the photons) compare favorably with standard techniques (which use all of them). Using the Fisher-information metric, we demonstrate that weak-value techniques can put all of the Fisher information about the detected parameter into a small portion of the events and show how this fact alone gives technical advantages. We go on to consider a time-correlated noise model and find that a Fisher-information analysis indicates that the …


Weak-Values Technique For Velocity Measurements, Gerardo I. Viza, Julián Martínez-Rincón, Gregory A. Howland, Hadas Frostig, Itay Shomroni, Barak Dayan, John C. Howell Aug 2013

Weak-Values Technique For Velocity Measurements, Gerardo I. Viza, Julián Martínez-Rincón, Gregory A. Howland, Hadas Frostig, Itay Shomroni, Barak Dayan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

In a recent Letter, Brunner and Simon proposed an interferometric scheme using imaginary weak values with a frequency-domain analysis to outperform standard interferometry in longitudinal phase shifts [Phys. Rev. Lett 105, 010405 (2010)]. Here we demonstrate an interferometric scheme combined with a time-domain analysis to measure longitudinal velocities. The technique employs the near-destructive interference of non-Fourier limited pulses, one Doppler shifted due to a moving mirror in a Michelson interferometer. We achieve a velocity measurement of 400  fm/s and show our estimator to be efficient by reaching its Cramér–Rao bound.


Einstein-Podolsky-Rosen Steering Inequalities From Entropic Uncertainty Relations, James Schneeloch, Curtis J. Broadbent, Stephen P. Walborn, Eric G. Cavalcanti, John C. Howell Jun 2013

Einstein-Podolsky-Rosen Steering Inequalities From Entropic Uncertainty Relations, James Schneeloch, Curtis J. Broadbent, Stephen P. Walborn, Eric G. Cavalcanti, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We use entropic uncertainty relations to formulate inequalities that witness Einstein-Podolsky-Rosen (EPR)-steering correlations in diverse quantum systems. We then use these inequalities to formulate symmetric EPR-steering inequalities using the mutual information. We explore the differing natures of the correlations captured by one-way and symmetric steering inequalities and examine the possibility of exclusive one-way steerability in two-qubit states. Furthermore, we show that steering inequalities can be extended to generalized positive operator-valued measures, and we also derive hybrid steering inequalities between alternate degrees of freedom.


Null Values And Quantum State Discrimination, Oded Zilberberg, Alessandro Romito, David J. Starling, Gregory A. Howland, Curtis J. Broadbent, John C. Howell, Yuval Gefen Apr 2013

Null Values And Quantum State Discrimination, Oded Zilberberg, Alessandro Romito, David J. Starling, Gregory A. Howland, Curtis J. Broadbent, John C. Howell, Yuval Gefen

Mathematics, Physics, and Computer Science Faculty Articles and Research

We present a measurement protocol for discriminating between two different quantum states of a qubit with high fidelity. The protocol, called null value, is comprised of a projective measurement performed on the system with a small probability (also known as partial collapse), followed by a tuned postselection. We report on an optical experimental implementation of the scheme. We show that our protocol leads to an amplified signal-to-noise ratio (as compared with a straightforward strong measurement) when discerning between the two quantum states.


Rapidly Reconfigurable Optically Induced Photonic Crystals In Hot Rubidium Vapor, Bethany Little, David J. Starling, John C. Howell, Raphael D. Cohen, David Shwa, Nadav Katz Apr 2013

Rapidly Reconfigurable Optically Induced Photonic Crystals In Hot Rubidium Vapor, Bethany Little, David J. Starling, John C. Howell, Raphael D. Cohen, David Shwa, Nadav Katz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Through periodic index modulation, we create two different types of photonic structures in a heated rubidium vapor for controlled reflection, transmission, and diffraction of light. The modulation is achieved through the use of the ac Stark effect resulting from a standing-wave control field. The periodic intensity structures create translationally invariant index profiles analogous to photonic crystals in spectral regions of steep dispersion. Experimental results are consistent with modeling.


Violation Of Continuous-Variable Einstein-Podolsky-Rosen Steering With Discrete Measurements, James Schneeloch, P. Ben Dixon, Gregory A. Howland, Curtis J. Broadbent, John C. Howell Mar 2013

Violation Of Continuous-Variable Einstein-Podolsky-Rosen Steering With Discrete Measurements, James Schneeloch, P. Ben Dixon, Gregory A. Howland, Curtis J. Broadbent, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this Letter, we derive an entropic Einstein-Podolsky-Rosen (EPR) steering inequality for continuous-variable systems using only experimentally measured discrete probability distributions and details of the measurement apparatus. We use this inequality to witness EPR steering between the positions and momenta of photon pairs generated in spontaneous parametric down-conversion. We examine the asymmetry between parties in this inequality, and show that this asymmetry can be used to reduce the technical requirements of experimental setups intended to demonstrate the EPR paradox. Furthermore, we develop a more stringent steering inequality that is symmetric between parties, and use it to show that the down-converted …


Efficient High-Dimensional Entanglement Imaging With A Compressive-Sensing Double-Pixel Camera, Gregory A. Howland, John C. Howell Oct 2012

Efficient High-Dimensional Entanglement Imaging With A Compressive-Sensing Double-Pixel Camera, Gregory A. Howland, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We implement a double-pixel compressive-sensing camera to efficiently characterize, at high resolution, the spatially entangled fields that are produced by spontaneous parametric down-conversion. This technique leverages sparsity in spatial correlations between entangled photons to improve acquisition times over raster scanning by a scaling factor up to n2/log(n) for n-dimensional images. We image at resolutions up to 1024 dimensions per detector and demonstrate a channel capacity of 8.4 bits per photon. By comparing the entangled photons’ classical mutual information in conjugate bases, we violate an entropic Einstein-Podolsky-Rosen separability criterion for all measured resolutions. More broadly, our result indicates that …


Double Lorentzian Atomic Prism, David J. Starling, Steven M. Bloch, Praveen K. Vudyasetu, Joseph S. Choi, Bethany Little, John C. Howell Aug 2012

Double Lorentzian Atomic Prism, David J. Starling, Steven M. Bloch, Praveen K. Vudyasetu, Joseph S. Choi, Bethany Little, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We present an atomic prism spectrometer that utilizes the steep linear dispersion between two strongly absorbing hyperfine resonances of rubidium. We resolve spectral lines 50 MHz apart and, utilizing a larger part of the available spectrum than only between the two resonances, we spatially separate collinear pump, signal, and idler beams resulting from a four-wave mixing process. Due to the high transparency possible between the resonances, these results have applications in the filtering of narrow-band entangled photons and interaction-free measurements.


Quantum Mutual Information Capacity For High-Dimensional Entangled States, P. Ben Dixon, Gregory A. Howland, James Schneeloch, John C. Howell Apr 2012

Quantum Mutual Information Capacity For High-Dimensional Entangled States, P. Ben Dixon, Gregory A. Howland, James Schneeloch, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

High-dimensional Hilbert spaces used for quantum communication channels offer the possibility of large data transmission capabilities. We propose a method of characterizing the channel capacity of an entangled photonic state in high-dimensional position and momentum bases. We use this method to measure the channel capacity of a parametric down-conversion state by measuring in up to 576 dimensions per detector. We achieve a channel capacity over 7  bits/photon in either the position or momentum basis. Furthermore, we provide a correspondingly high-dimensional separability bound that suggests that the channel performance cannot be replicated classically.


Entangled-Photon Compressive Ghost Imaging, Petros Zerom, Kam Wai Clifford Chan, John C. Howell, Robert W. Boyd Dec 2011

Entangled-Photon Compressive Ghost Imaging, Petros Zerom, Kam Wai Clifford Chan, John C. Howell, Robert W. Boyd

Mathematics, Physics, and Computer Science Faculty Articles and Research

We have experimentally demonstrated high-resolution compressive ghost imaging at the single-photon level using entangled photons produced by a spontaneous parametric down-conversion source and using single-pixel detectors. For a given mean-squared error, the number of photons needed to reconstruct a two-dimensional image is found to be much smaller than that in quantum ghost imaging experiments employing a raster scan. This procedure not only shortens the data acquisition time, but also suggests a more economical use of photons for low-light-level and quantum image formation.


Theoretical Analysis Of Quantum Ghost Imaging Through Turbulence, Kam Wai Clifford Chan, D. S. Simon, A. V. Sergienko, Nicholas D. Hardy, Jeffrey H. Shapiro, P. Ben Dixon, Gregory A. Howland, John C. Howell, Joseph H. Eberly, Malcolm N. O'Sullivan, Brandon Rodenburg, Robert W. Boyd Oct 2011

Theoretical Analysis Of Quantum Ghost Imaging Through Turbulence, Kam Wai Clifford Chan, D. S. Simon, A. V. Sergienko, Nicholas D. Hardy, Jeffrey H. Shapiro, P. Ben Dixon, Gregory A. Howland, John C. Howell, Joseph H. Eberly, Malcolm N. O'Sullivan, Brandon Rodenburg, Robert W. Boyd

Mathematics, Physics, and Computer Science Faculty Articles and Research

Atmospheric turbulence generally affects the resolution and visibility of an image in long-distance imaging. In a recent quantum ghost imaging experiment [P. B. Dixon et al., Phys. Rev. A 83, 051803 (2011)], it was found that the effect of the turbulence can nevertheless be mitigated under certain conditions. This paper gives a detailed theoretical analysis to the setup and results reported in the experiment. Entangled photons with a finite correlation area and a turbulence model beyond the phase screen approximation are considered.


Extracting An Entanglement Signature From Only Classical Mutual Information, David J. Starling, Curtis J. Broadbent, John C. Howell Sep 2011

Extracting An Entanglement Signature From Only Classical Mutual Information, David J. Starling, Curtis J. Broadbent, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We introduce a quantity which is formed using classical notions of mutual information and which is computed using the results of projective measurements. This quantity constitutes a sufficient condition for entanglement and represents the amount of information that can be extracted from a bipartite system for spacelike separated observers. In addition to discussion, we provide simulations as well as experimental results for the singlet and maximally correlated mixed states.


Quantum Ghost Imaging Through Turbulence, John C. Howell May 2011

Quantum Ghost Imaging Through Turbulence, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We investigate the effect of turbulence on quantum ghost imaging. We use entangled photons and demonstrate that for a specific experimental configuration the effect of turbulence can be greatly diminished. By decoupling the entangled photon source from the ghost-imaging central image plane, we are able to dramatically increase the ghost-image quality. When imaging a test pattern through turbulence, this method increases the imaged pattern visibility from V=0.15±0.04 to 0.42±0.04.


Experimental Violation Of Two-Party Leggett-Garg Inequalities With Semiweak Measurements, Justin Dressel, Curtis J. Broadbent, John C. Howell, Andrew N. Jordan Jan 2011

Experimental Violation Of Two-Party Leggett-Garg Inequalities With Semiweak Measurements, Justin Dressel, Curtis J. Broadbent, John C. Howell, Andrew N. Jordan

Mathematics, Physics, and Computer Science Faculty Articles and Research

We generalize the derivation of Leggett-Garg inequalities to systematically treat a larger class of experimental situations by allowing multiparticle correlations, invasive detection, and ambiguous detector results. Furthermore, we show how many such inequalities may be tested simultaneously with a single setup. As a proof of principle, we violate several such two-particle inequalities with data obtained from a polarization-entangled biphoton state and a semiweak polarization measurement based on Fresnel reflection. We also point out a nontrivial connection between specific two-party Leggett-Garg inequality violations and convex sums of strange weak values.


Precision Frequency Measurements With Interferometric Weak Values, David J. Starling, P. Ben Dixon, Andrew N. Jordan, John C. Howell Dec 2010

Precision Frequency Measurements With Interferometric Weak Values, David J. Starling, P. Ben Dixon, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We demonstrate an experiment which utilizes a Sagnac interferometer to measure a change in optical frequency of 129 ± 7 kHz/√Hz with only 2 mW of continuous-wave, single-mode input power. We describe the measurement of a weak value and show how even higher-frequency sensitivities may be obtained over a bandwidth of several nanometers. This technique has many possible applications, such as precision relative frequency measurements and laser locking without the use of atomic lines.


Rapidly Reconfigurable Slow-Light System Based On Off-Resonant Raman Absorption, Praveen K. Vudyasetu, Ryan M. Camacho, John C. Howell Nov 2010

Rapidly Reconfigurable Slow-Light System Based On Off-Resonant Raman Absorption, Praveen K. Vudyasetu, Ryan M. Camacho, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We present a slow-light system based on dual Raman absorption resonances in warm rubidium vapor. Each Raman absorption resonance is produced by a control beam in an off-resonant Λ system. This system combines all optical control of the Raman absorption and the low-dispersion broadening properties of the double Lorentzian absorption slow light. The bandwidth, group delay, and central frequency of the slow-light system can all be tuned dynamically by changing the properties of the control beam. We demonstrate multiple pulse delays with low distortion and show that such a system has fast switching dynamics and thus fast reconfiguration rates.


Heralded Single-Photon Partial Coherence, P. Ben Dixon, Gregory A. Howland, Mehul Malik, David J. Starling, R. W. Boyd, John C. Howell Aug 2010

Heralded Single-Photon Partial Coherence, P. Ben Dixon, Gregory A. Howland, Mehul Malik, David J. Starling, R. W. Boyd, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We study transverse spatial coherence of approximately localized single-photon states. We demonstrate nonlocal control over single-photon spatial coherence via projective measurements of an entangled twin and provide a theoretical interpretation from quantum coherence theory. Our results show that the spatial coherence of a single-photon state behaves similarly to that of a classical optical field, although the coincidence measurement adds a degree of freedom.


Interferometric Weak Value Deflections: Quantum And Classical Treatments, John C. Howell, David J. Starling, P. Ben Dixon, Praveen K. Vudyasetu, Andrew N. Jordan Mar 2010

Interferometric Weak Value Deflections: Quantum And Classical Treatments, John C. Howell, David J. Starling, P. Ben Dixon, Praveen K. Vudyasetu, Andrew N. Jordan

Mathematics, Physics, and Computer Science Faculty Articles and Research

We derive the weak value deflection given in an article by Dixon et al. [P. B. Dixon et al. Phys. Rev. Lett. 102 173601 (2009)] both quantum mechanically and classically, including diffraction effects. This article is meant to cover some of the mathematical details omitted in that article owing to space constraints.


Continuous Phase Amplification With A Sagnac Interferometer, David J. Starling, P. Ben Dixon, Nathan S. Williams, Andrew N. Jordan, John C. Howell Oct 2009

Continuous Phase Amplification With A Sagnac Interferometer, David J. Starling, P. Ben Dixon, Nathan S. Williams, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We describe a phase-amplification technique using a Sagnac interferometer. We monitor the relative phase between two paths of a precisely misaligned interferometer by measuring the average position of a split-Gaussian mode in the dark port. Although we monitor only the dark port, we show that the signal varies linearly with phase and that we can obtain similar sensitivity to balanced homodyne detection. We derive the source of the amplification using classical wave optics.


Optimizing The Signal-To-Noise Ratio Of A Beam-Deflection Measurement With Interferometric Weak Values, David J. Starling, P. Ben Dixon, Andrew N. Jordan, John C. Howell Oct 2009

Optimizing The Signal-To-Noise Ratio Of A Beam-Deflection Measurement With Interferometric Weak Values, David J. Starling, P. Ben Dixon, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

The amplification obtained using weak values is quantified through a detailed investigation of the signal-to-noise ratio for an optical beam-deflection measurement. We show that for a given deflection, input power and beam radius, the use of interferometric weak values allows one to obtain the optimum signal-to-noise ratio using a coherent beam. This method has the advantage of reduced technical noise and allows for the use of detectors with a low saturation intensity. We report on an experiment which improves the signal-to-noise ratio for a beam-deflection measurement by a factor of 54 when compared to a measurement using the same beam …


Ultrasensitive Beam Deflection Measurement Via Interferometric Weak Value Amplification, P. Ben Dixon, David J. Starling, Andrew N. Jordan, John C. Howell Apr 2009

Ultrasensitive Beam Deflection Measurement Via Interferometric Weak Value Amplification, P. Ben Dixon, David J. Starling, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report on the use of an interferometric weak value technique to amplify very small transverse deflections of an optical beam. By entangling the beam’s transverse degrees of freedom with the which-path states of a Sagnac interferometer, it is possible to realize an optical amplifier for polarization independent deflections. The theory for the interferometric weak value amplification method is presented along with the experimental results, which are in good agreement. Of particular interest, we measured the angular deflection of a mirror down to 400


All Optical Waveguiding In A Coherent Atomic Rubidium Vapor, Praveen K. Vudyasetu, David J. Starling, John C. Howell Mar 2009

All Optical Waveguiding In A Coherent Atomic Rubidium Vapor, Praveen K. Vudyasetu, David J. Starling, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We demonstrate an all optical waveguide imprinted by a low power Laguerre Gaussian control laser beam using a coherent Raman process in warm atomic rubidium vapor. We show that the signal beam propagates with a small spot size over several diffraction lengths. We also show that the coupling efficiency of the signal beam into the waveguide varies linearly with the signal power.


Realization Of An All-Optical Zero To Cross-Phase Modulation Jump, Ryan M. Camacho, P. Ben Dixon, Ryan T. Glasser, Andrew N. Jordan, John C. Howell Jan 2009

Realization Of An All-Optical Zero To Cross-Phase Modulation Jump, Ryan M. Camacho, P. Ben Dixon, Ryan T. Glasser, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report on the experimental demonstration of an all-optical π cross-phase modulation jump. By performing a preselection, an optically induced unitary transformation, and then a postselection on the polarization degree of freedom, the phase of the output beam acquires either a zero or π phase shift (with no other possible values). The postselection results in optical loss in the output beam. An input state may be chosen near the resulting phase singularity, yielding a π phase shift even for weak interaction strengths. The scheme is experimentally demonstrated using a coherently prepared dark state in a warm atomic cesium vapor.


Discriminating Orthogonal Single-Photon Images, Curtis J. Broadbent, Petros Zerom, Heedeuk Shin, John C. Howell, Robert W. Boyd Jul 2008

Discriminating Orthogonal Single-Photon Images, Curtis J. Broadbent, Petros Zerom, Heedeuk Shin, John C. Howell, Robert W. Boyd

Mathematics, Physics, and Computer Science Faculty Articles and Research

We can encode an image from an orthogonal basis set onto a single photon from a downconverted pair via the use of an amplitude mask. We can then discriminate the image imprinted on the photon from other images in the set using holographic-matched filtering techniques. We demonstrate this procedure experimentally for an image space of two objects, and we discuss the possibility of applying this method to a much larger image space. This process could have important implications for the manipulation of images at the quantum level.


Preservation Of Energy-Time Entanglement In A Slow Light Medium, Curtis J. Broadbent, Ryan M. Camacho, Ran Xin, John C. Howell Apr 2008

Preservation Of Energy-Time Entanglement In A Slow Light Medium, Curtis J. Broadbent, Ryan M. Camacho, Ran Xin, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We demonstrate the preservation of entanglement of an energy-time entangled biphoton through a slow light medium. Using the D1 and D2 fine structure resonances of Rubidium, we delay one photon of the 1.5 THz biphoton by ∼1.3 correlation lengths and measure the fourth order correlation fringes. After the group delay the fringe visibility is reduced from 97.0±4.4% to 80.0±4.8%, but is still sufficient to violate a Bell inequality. We show that temporal broadening is the primary mechanism for reducing the fringe visibility and that smaller bandwidths lead to greatly reduced broadening.


Storage And Retrieval Of Multimode Transverse Images In Hot Atomic Rubidium Vapor, Praveen K. Vudyasetu, Ryan M. Camacho, John C. Howell Mar 2008

Storage And Retrieval Of Multimode Transverse Images In Hot Atomic Rubidium Vapor, Praveen K. Vudyasetu, Ryan M. Camacho, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report on the experimental realization of the storage of images in a hot vapor of Rubidium atoms. The images are stored in and retrieved from the long-lived ground state atomic coherences. We show that an image impressed onto a 500 ns pulse can be stored and retrieved up to 30  μs later. The image storage is made robust to diffusion by storing the Fourier transform of the image.


Slow-Light Fourier Transform Interferometer, Zhimin Shi, Robert W. Boyd, Ryan M. Camacho, Praveen K. Vudyasetu, John C. Howell Dec 2007

Slow-Light Fourier Transform Interferometer, Zhimin Shi, Robert W. Boyd, Ryan M. Camacho, Praveen K. Vudyasetu, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We describe a new type of Fourier transform (FT) interferometer in which the tunable optical delay between the two arms is realized by using a continuously variable slow-light medium instead of a moving arm as in a conventional setup. The spectral resolution of such a FT interferometer exceeds that of a conventional setup of comparable size by a factor equal to the maximum group index of the slow-light medium. The scheme is experimentally demonstrated by using a rubidium atomic vapor cell as the tunable slow-light medium, and the spectral resolution is enhanced by a factor of approximately 100.