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Search Publications by: Varun Verma (Fed)

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Displaying 26 - 50 of 76

Quantum Frequency Conversion of a Quantum Dot Single-Photon Source on a Nanophotonic Chip

May 20, 2019
Author(s)
Anshuman Singh, Qing Li, Shunfa Liu, Ying Yu, Xiyuan Lu, Christian Schneider, Sven Hofling, John Lawall, Varun Verma, Richard Mirin, Sae Woo Nam, Jin Liu, Kartik Srinivasan
Single self-assembled InAs/GaAs quantum dots are promising bright sources of indistinguishable photons for quantum information science. However, their distribution in emission wavelength, due to inhomogeneous broadening inherent to their growth, has

Towards a source of entangled photon pairs in gallium phosphide

May 9, 2019
Author(s)
Paulina S. Kuo, Peter G. Schunemann, Mackenzie Van Camp, Varun B. Verma, Thomas Gerrits, Sae Woo Nam, Richard P. Mirin
We investigate parametric down-conversion in orientation-patterned GaP. Pumped at 865 nm, the signal and idler are at 1350 nm and 2400 nm, respectively.

Generating polarization-entangled photon pairs in domain-engineered PPLN

May 7, 2019
Author(s)
Paulina S. Kuo, Varun B. Verma, Thomas Gerrits, Sae Woo Nam, Richard P. Mirin
Using a periodically poled LiNbO3 crystal that is domain-engineered for two simultaneous type-II down-conversion processes, we demonstrated polarization-entangled photon-pair generation.

Single self-assembled InAs/GaAs quantum dots in photonic nanostructures: the role of nanofabrication

June 13, 2018
Author(s)
Jin Liu, Kumarasiri Konthasinghe, Marcelo I. Davanco, John Lawall, Vikas Anant, Varun Verma, Richard Mirin, Jin Dong Song, Ben Ma, Ze Sheng Chen, Hai Qiao Ni, Zhi Chuan Niu, Kartik Srinivasan
Single self-assembled InAs/GaAs quantum dots are a promising solid-state quantum technology, with vacuum Rabi splitting, single-photon-level nonlinearities, and bright, pure, and indistinguishable single-photon generation having been demonstrated. In such

Short-wave infrared compressive imaging of single photons

June 6, 2018
Author(s)
Thomas Gerrits, Daniel Lum, Varun B. Verma, John Howell, Richard P. Mirin, Sae Woo Nam
We present a short-wave infrared (SWIR) single photon camera based on a single superconducting nanowire single photon detector (SNSPD) and compressive imaging. We show SWIR single photon imaging at a megapixel resolution with a low signal-to-background

UV superconducting nanowire single-photondetectors with high efficiency, low noise, and4 K operating temperature

October 18, 2017
Author(s)
Varun Verma, Adriana Lita, Richard Mirin, Sae Woo Nam, Emma Wollman, Andrew Beyer, Ryan Briggs, Francesco Marsili, Jason Allmaras, Matthew Shaw
For photon-counting applications at ultraviolet wavelengths, there are currently nodetectors that combine high efficiency (> 50%), sub-nanosecond timing resolution, and sub-Hz dark count rates. Superconducting nanowire single-photon detectors (SNSPDs) have

Heterogeneous integration for on-chip quantum photonic circuits with single quantum dot devices

October 12, 2017
Author(s)
Marcelo I. Davanco, Liu Jin, Luca Sapienza, Chen-Zhao Zhang, Jose Vinicius De Miranda Cardoso, Varun B. Verma, Richard P. Mirin, Sae Woo Nam, Liu Liu, Kartik A. Srinivasan
Photonic integration is establishing itself as an enabling technology for photonic quantum science, offering considerably greater scalability, stability, and functionality than traditional bulk optics. Here, we develop a scalable, heterogeneous III-V /

Towards integrated superconducting detectors on lithium niobate waveguides

August 29, 2017
Author(s)
Jan P. Hoepker, Moritz Bartnick, Evan Meyer-Scott, Frederik Thiele, Stephan Krapick, Nicola Montaut, Matteo Santandrea, Harald Herrmann, Sebastian Lengeling, Raimund Ricken, Victor Quiring, Torsten Meier, Adriana Lita, Varun Verma, Thomas Gerrits, Sae Woo Nam, Christine Silberhorn, Tim J. Bartley
Superconducting detectors are now well-established tools for low-light optics, and in particular quantum optics, boasting high-efficiency, fast response and low noise. Similarly, lithium niobate is an important platform for integrated optics given its

Fano fluctuations in superconducting nanowire single-photon detectors

August 9, 2017
Author(s)
Alex Kozorezov, Colin Lambert, Francesco Marsili, Marty Stevens, Varun Verma, Matthew Shaw, Richard Mirin
Because of their universal nature, Fano fluctuations are expected to play an important role in the behavior of superconducting nanowire single-photon detectors (SNSPDs). Taking into account Fano fluctuations we predict that the photon counting rate as a

Mid-infrared laser-induced fluorescence with nanosecond time resolution using a superconducting nanowire single-photon detector: New technology for molecular science

June 2, 2017
Author(s)
Li Chen, Dirk Schwarzer, Varun Verma, Marty Stevens, Francesco F. Marsili, Richard Mirin, Sae Woo Nam, Alec M. Wodtke
In contrast to UV photomultiplier tubes widely used in physical chemistry, mid- infrared detectors are notorious for poor sensitivity and slow time response. This helps explain why, despite the importance of infrared spectroscopy in molecular science, mid

Bandwidth-enhanced superconducting nanowire single photon detectors for telecom wavelengths

May 13, 2017
Author(s)
Stephan Krapick, Marina Hesselberg, Varun Verma, Igor Vayshenker, Sae Woo Nam, Richard Mirin
We present a single-photon detector providing system detection efficiencies of at least (86.7 ± 0.9) % from 1450 nm to 1640 nm. It comprises bilayer superconducting WSi nanowires in conjunction with all-dielectric structures for optical impedance matching

UV-sensitive superconducting nanowire single photon detectors for integration in an ion trap

April 17, 2017
Author(s)
Daniel H. Slichter, Varun B. Verma, Dietrich G. Leibfried, Richard P. Mirin, Sae Woo Nam, David J. Wineland
We demonstrate superconducting nanowire single photon detectors with 76 +/- 4% system detection efficiency at a wavelength of 315 nm and an operating temperature of 3.2 K, with a background count rate below 1 count per second at saturated detection

A quantum enigma machine: Experimentally demonstrating quantum data locking

August 12, 2016
Author(s)
Daniel Lum, Michael S. Allman, Thomas Gerrits, Cosmo Lupo, Seth Lloyd, Varun Verma, Sae Woo Nam, John Howell
During the first half of the 20th century, enigma machines (i.e., pseudorandom polyalphabetic ciphers) of increasing sophistication gave better resistance against brute-force codebreaking attacks. However, the ultimate form of cryptographic security is

Demonstration of EPR steering using single-photon path entanglement and displacement-based detection

August 12, 2016
Author(s)
T Guerreiro, F. Monteiro, A Martin, J B. Brask, T Vertesi, Boris Korzh, Felix Bussieres, Varun Verma, Adriana Lita, Richard Mirin, Sae Woo Nam, Francesco Marsili, Matthew D. Shaw, Nicolas Gisin, Nicolas Brunner, Hugo Zbinden, Robert Thew
We demonstrate the violation of an EPR steering inequality developed for single photon path entanglement with displacement-based detection. We use a high-rate source of heralded single-photon path-entangled states, combined with high efficiency

Experimental investigation of the detection mechanism in WSi nanowire superconducting single photon detectors

July 18, 2016
Author(s)
Rosalinda Gaudio, Jelmer J. Renema, Zili Zhou, Varun Verma, Jeff Shainline, Martin Stevens, Richard Mirin, Sae Woo Nam, Martin P. van Exter, Michiel J. de Dood, Andrea Fiore
We use quantum detector tomography to investigate the detection mechanism in WSi nanowire superconducting single photon detectors (SSPDs). To this purpose, we fabricated a 250 nm wide and 250 nm long WSi nanowire and measured its response to impinging

Athermal avalanche in bilayer superconducting nanowire single-photon detectors

March 28, 2016
Author(s)
Varun B. Verma, Martin J. Stevens, Richard P. Mirin, Sae Woo Nam
We demonstrate that two superconducting nanowires separated by a thin insulating barrier can undergo a thermal avalanche process. In this process, Joule heating caused by a photodetection event in one nanowire and the associated production of athermal

Hotspot Relaxation Dynamics in a Current Carrying Superconductor

March 17, 2016
Author(s)
Francesco Marsili, Martin Stevens, Alex Kozorezov, Varun Verma, Colin Lambert, Jeffrey A. Stern, Rob Horansky, Shellee D. Dyer, Shannon Duff, David P. Pappas, Matthew Shaw, Richard Mirin, Sae Woo Nam
When a photon is absorbed in a superconductor it creates a region of nonequilibrium superconductivity referred to as a hotspot [1]. The operation of most superconducting single photon detectors (microwave kinetic inductance detectors, MKIDs [2,3]

High-efficiency superconducting nanowire single-photon detectors fabricated from MoSi thin-films

December 22, 2015
Author(s)
Varun B. Verma, Boris Korzh, Felix Bussieres, Robert D. Horansky, Shellee D. Dyer, Adriana E. Lita, Igor Vayshenker, Francesco Marsili, Matthew D. Shaw, Hugo Zbinden, Richard P. Mirin, Sae Woo Nam
We report on MoSi SNSPDs which achieved high system detection efficiency (87.1 ± 0.5% at 1542 nm) at 0.7 K and we demonstrate that these detectors can also be operated with saturated internal efficiency at a temperature of 2.3 K in a Gifford-McMahon

A strong loophole-free test of local realism

December 16, 2015
Author(s)
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