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Search Publications by: Varun Verma (Fed)

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Displaying 1 - 25 of 78

Superconducting Nanowire Single-Photon Detector Arrays for the Near- to Mid-Infrared

October 31, 2023
Author(s)
Benedikt Hampel, Richard Mirin, Sae Woo Nam, Varun Verma
Superconducting Nanowire Single-Photon Detectors (SNSPDs) are excellent devices for the analysis of faint light from the ultraviolet to the mid-infrared. Recent developments push their broad wavelength bandwidth further into the mid-infrared towards 20 μm

Trap-Integrated Superconducting Nanowire Single-Photon Detectors with Improved RF Tolerance for Trapped-Ion Qubit State Readout

April 24, 2023
Author(s)
Benedikt Hampel, Daniel Slichter, Dietrich Leibfried, Richard Mirin, Sae Woo Nam, Varun Verma
State readout of trapped-ion qubits with trap-integrated detectors can address important challenges for scalable quantum computing, but the strong radio frequency (rf) electric fields used for trapping can impact detector performance. Here, we report on

Picosecond-resolution single-photon time lens for temporal mode quantum processing

March 28, 2022
Author(s)
Chaitali Joshi, Ben Sparkes, Alessandro Farsi, Thomas Gerrits, Sae Woo Nam, Varun Verma, Sven Ramelow, Alex Gaeta
Techniques to control the spectro-temporal properties of quantum states of light at ultrafast time scales are crucial for several applications in quantum information science. In this work, we report an all-optical time lens based on Bragg-scattering four

Laser-lithographically written micron-wide superconducting nanowire single-photon detectors

March 23, 2022
Author(s)
Maximilian Protte, Varun Verma, Jan Philipp Hopker, Richard Mirin, Sae Woo Nam, Tim Bartley
In this paper, we demonstrate our results on micron-wide tungsten silicide superconducting nanowire single-photon detectors fabricated by laser lithography. Laser-lithographically written devices allow for fast and easy structuring of large areas while

Single-photon detection in the mid-infrared up to 10 micron wavelength using tungsten silicide superconducting nanowire detectors

September 14, 2021
Author(s)
Varun Verma, Adriana Lita, Yao Zhai, Heli C. Vora, Richard Mirin, Sae Woo Nam, Boris Korzh, Alex Walter, Ryan Briggs, Marco Colangelo, Emma Wollman, Andrew Beyer, Jason Allmaras, D. Zhu, Ekkehart Schmidt, A. G. Kozorezov, Matthew Shaw
We developed superconducting nanowire single-photon detectors (SNSPDs) based on tungsten silicide (WSi) that show saturated internal detection efficiency up to a wavelength of 10 um. These detectors are promising for applications in the mid-infrared

Integrated superconducting nanowire single-photon detectors on titanium in-diffused lithium niobate waveguides

July 28, 2021
Author(s)
Varun Verma, Richard Mirin, Sae Woo Nam, Jan P. Hoepker, Maximilian Protte, Raimund Ricken, Victor Quiring, Christof Eigner, Christine Silberhorn, Tim J. Bartley
We demonstrate the integration of amorphous tungsten silicide superconducting nanowire single- photon detectors on titanium in-diffused lithium niobate waveguides. We show proof-of-principle detection of evanescently-coupled photons of wavelength 1550nm

Recent advances in superconducting nanowire single-photon detector technology for exoplanet transit spectroscopy in the mid-infrared

January 12, 2021
Author(s)
Varun Verma, Jeff Chiles, Adriana Lita, Richard Mirin, Sae Woo Nam, Yao Zhai, Adam McCaughan, Emma Wollman, Alexander Walter, Boris Korzh, Jason Allmaras, Ekkehart Schmidt, S. Frasca, Matthew Shaw
Superconducting nanowire single-photon detectors, or SNSPDs, have become the highest-performing class of single-photon detectors in the near-IR. At telecom wavelengths, SNSPDs have demonstrated detection effi- ciency above 95%, intrinsic dark count rates

State Readout of a Trapped Ion Qubit Using a Trap-integrated Superconducting Photon Detector

January 6, 2021
Author(s)
Susanna L. Todaro, Varun Verma, Katherine C. McCormick, David T. Allcock, Richard Mirin, David J. Wineland, Sae Woo Nam, Andrew C. Wilson, Dietrich Leibfried, Daniel Slichter
We detect fluorescence photons emitted by a single $^9$Be$^+$ ion confined in a surface- electrode rf ion trap, using a superconducting nanowire single photon detector integrated directly into the trap. We achieve a qubit readout fidelity of 99.91(1) %

Superconducting microwire detectors with single-photon sensitivity in the near-infrared

June 16, 2020
Author(s)
Jeffrey T. Chiles, Sonia M. Buckley, Adriana E. Lita, Varun B. Verma, Jeffrey M. Shainline, Richard P. Mirin, Sae Woo Nam, Jason Allmaras, Boris Korzh, Emma Wollman, Matthew Shaw
We report on the fabrication and characterization of single-photon-sensitive WSi superconducting detectors with wire widths from 1 υm to 3 υm. The devices achieve saturated internal detection efficiency at 1.55 υm wavelength and exhibit maximum count rates

Observation of an isomerizing double-well quantum system in the condensed phase

January 10, 2020
Author(s)
Varun Verma, Jascha A. Lau, Arnab Choudhury, Li Chen, Dirk Schwarzer, Alec M. Wodtke
Molecules are quantum objects; therefore, isomerization fundamentally involves quantum states bound within a molecular potential energy function with multiple minima. For isolated gas-phase molecules, eigenstates well above the isomerization saddle points

Tunable quantum beat of single photons enabled by nonlinear nanophotonics

November 22, 2019
Author(s)
Qing Li, Anshuman Singh, Xiyuan Lu, John Lawall, Varun Verma, Richard Mirin, Sae Woo Nam, Kartik Srinivasan
Integrated photonics is a promising approach for scalable implementation of diverse quantum resources at the chip-scale. Here, we demonstrate the integration of two essential building blocks for quantum information science - quantum sources and frequency

A kilopixel array of superconducting nanowire single-photon detectors

November 18, 2019
Author(s)
Varun Verma, Adriana Lita, Sae Woo Nam, R P. Mirin, Emma Wollman, William Farr, Matthew Shaw
We present a 1024-element imaging array of superconducting nanowire single photon detectors (SNSPDs) using a 32x32 row-column multiplexing architecture. Large arrays are desirable for applications such as imaging, spectroscopy, or particle detection.

Detecting Sub-GeV Dark Matter with Superconducting Nanowires

October 10, 2019
Author(s)
Varun Verma, Sae Woo Nam, Ilya Charaev, Marco Colangelo, Karl Berggren, Yonit Hochberg
We propose the use of superconducting nanowires as both target and sensor for direct detection of light dark matter. With excellent sensitivity to low-energy deposits on electrons, and demonstrated low dark counts, such devices could be used to probe