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Search Publications by: Krister Shalm (Fed)

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Displaying 1 - 12 of 12

Development and Evaluation of Bluetooth Low-Energy Device for Electronic Encounter Metrics

January 20, 2022
Katy Keenan, Joe Aumentado, Harold Booth, Kimberly Briggman, Mikail Kraft-Molleda, Michele Martin, Rene Peralta, Angela Robinson, Krister Shalm, Michelle Stephens, Emily Townsend, Sae Woo Nam
The coronavirus disease 2019 (COVID-19) pandemic led to the need for tracking of physical contacts and potential exposure to disease. Traditional contact tracing can be augmented by electronic tools called "electronic contact tracing" or "exposure

Demonstration that Einstein-Podolsky-Rosen Steering Requires More than One Bit of Faster-than-Light Information Transmission

May 28, 2021
Yu Xiang, Michael Mazurek, Joshua Bienfang, Michael Wayne, Carlos Abellan, Waldimar Amaya, Morgan Mitchell, Richard Mirin, Sae Woo Nam, Qiongyi He, Marty Stevens, Krister Shalm, Howard Wiseman
Schrödinger held that a local quantum system has some objectively real quantum state and no other (hidden) properties. He therefore took the Einstein-Podolsky-Rosen (EPR) phenomenon, which he generalized and called 'steering', to require nonlocal

Experimental Low-Latency Device-Independent Quantum Randomness

January 10, 2020
Yanbao Zhang, Lynden K. Shalm, Joshua C. Bienfang, Martin J. Stevens, Michael D. Mazurek, Sae Woo Nam, Carlos Abellan, Waldimar Amaya, Morgan Mitchell, Honghao Fu, Carl A. Miller, Alan Mink, Emanuel H. Knill
Applications of randomness such as private key generation and public randomness beacons require small blocks of certified random bits on demand. Device-independent quantum randomness can produce such random bits, but existing quantum-proof protocols and

Experimentally Generated Random Numbers Certified by the Impossibility of Superluminal Signaling

April 11, 2018
Peter L. Bierhorst, Emanuel H. Knill, Scott C. Glancy, Yanbao Zhang, Alan Mink, Stephen P. Jordan, Andrea Rommal, Yi-Kai Liu, Bradley Christensen, Sae Woo Nam, Martin J. Stevens, Lynden K. Shalm
From dice to modern complex circuits, there have been many attempts to build increasingly better devices to generate random numbers. Today, randomness is fundamental to security and cryptographic systems, as well as safeguarding privacy. A key challenge

Coherent quantum frequency bridge: phase preserving, nearly-noiseless parametric frequency converter

May 3, 2017
Ivan A. Burenkov, Yu-Hsiang Cheng, Tim O. Thomay, Glenn S. Solomon, Alan L. Migdall, Thomas Gerrits, Adriana E. Lita, Sae Woo Nam, Lynden K. Shalm, Sergey V. Polyakov
We characterize an efficient and nearly-noiseless parametric frequency upconverter. The ultra- low noise regime is reached by the wide spectral separation between the input and pump frequencies and the low pump frequency relative to the input photons. The

A significant-loophole-free test of Bell's theorem with entangled photons

December 16, 2015
Marissa Giustina, Marijn Versteegh, Soren Wengerowsky, Johannes Handsteiner, Armin Hochrainer, Kevin Phelan, Fabian Steinlechner, Johannes Koffler, Larsson Jan-Ake, Carlos Abellan, Waldimar Amaya, Valerio Pruneri, Morgan Mitchell, Joern Beyer, Thomas Gerrits, Adriana Lita, Krister Shalm, Sae Woo Nam, Thomas Scheidl, Rupert Ursin, Bernhard Wittmann, Anton Zeilinger
Local realism is the worldview in which physical properties of objects exist independently of measurement and where physical influences cannot travel faster than the speed of light. Bell's theorem states that this worldview is incompatible with the

A strong loophole-free test of local realism

December 16, 2015
Lynden K. Shalm, Evan Meyer-Scott, B. G. Christensen, Peter L. Bierhorst, Michael A. Wayne, Deny Hamel, Martin J. Stevens, Thomas Gerrits, Scott C. Glancy, Michael S. Allman, Kevin J. Coakley, Shellee D. Dyer, Adriana E. Lita, Varun B. Verma, Joshua C. Bienfang, Alan L. Migdall, Yanbao Zhang, William Farr, Francesco Marsili, Matthew D. Shaw, Jeffrey Stern, Carlos Abellan, Waldimar Amaya, Valerio Pruneri, Thomas Jennewein, Morgan Mitchell, P. G. Kwiat, Richard P. Mirin, Emanuel H. Knill, Sae Woo Nam
We present a loophole-free violation of local realism using entangled photon pairs. We ensure that all relevant events in our Bell test are spacelike separated by placing the parties far enough apart and by using fast random number generators and high

Analysis of coincidence-time loopholes in experimental Bell tests

March 4, 2015
B. G. Christensen, A. Hill, P. G. Kwiat, Emanuel Knill, Sae Woo Nam, Kevin Coakley, Scott Glancy, Krister Shalm, Y. Zhang
We apply a distance-based Bell-test analysis method ["Bell inequalities for continuously emitting sources" E. Knill et al. arXiv:14097732 (2014)] to three experimental data sets where conventional analyses failed or required additional assumptions. The

Spectral Correlation Measurements at the Hong-Ou-Mandel Interference Dip

January 22, 2015
Thomas Gerrits, Francesco Marsili, Varun B. Verma, Lynden K. Shalm, Jeffrey A. Stern, Matthew Shaw, Richard P. Mirin, Sae Woo Nam
We present an efficient tool capable of measuring the spectral correlations between photons emerging from a Hong-Ou-Mandel interference configuration. We show that the Hong-Ou-Mandel interference visibility decreases as the photons’ frequency spread is

Direct generation of three-photon polarization entanglement

April 28, 2014
Deny Hamel, Krister Shalm, Hannes Hubel, Aaron J. Miller, Francesco F. Marsili, Varun Verma, Richard Mirin, Sae Woo Nam, Kevin Resch, Thomas Jennewein
Non-classical states of light are of fundamental importance for emerging quantum technologies. All optics experiments producing multi-qubit entangled states have until now relied on outcome post-selection, a procedure where only the measurement results

Time-resolved double-slit interference pattern measurement with entangled photons

April 28, 2014
Lynden K. Shalm, Thomas Jennewein, Kevin Resch, Piotr Kolenderski, Carmelo Scarcella, Kelsey D. Johnsen Johnsen, Deny Hamel, Cahterine Holloway, Simone Tisa, Alberto Tosi
The double-slit experiment strikingly demonstrates the wave-particle duality of quantum objects. In this famous experiment, particles pass one-by-one through a pair of slits and are detected on a distant screen. A distinct wave-like pattern emerges after

Detection-Loophole-Free Test of Quantum Nonlocality, and Applications

September 26, 2013
B. G. Christensen, Kevin McCusker, Joseph Altepeter, Brice R. Calkins, Thomas Gerrits, Adriana Lita, Aaron J. Miller, Krister Shalm, Sae Woo Nam, P. G. Kwiat
We present a source of entangled photons that violates a Bell inequality free of the "fair-sampling" assumption, by over 50 standard deviations, and with enough "efficiency" overhead to eventually perform a fully loophole-free test of local realism. The