154 research outputs found
High intrinsic energy resolution photon number resolving detectors
Transition Edge Sensors (TESs) are characterized by the intrinsic figure of
merit to resolve both the energy and the statistical distribution of the
incident photons. These properties lead TES devices to become the best single
photon detector for quantum technology experiments. For a TES based on titanium
and gold has been reached, at telecommunication wavelength, an unprecedented
intrinsic energy resolution (0.113 eV). The uncertainties analysis of both
energy resolution and photon state assignment has been discussed. The thermal
properties of the superconductive device have been studied by fitting the bias
curve to evaluate theoretical limit of the energy resolution
Single-photon light detection with transition-edge sensors
Transition-Edge Sensors (TESs) are microcalorimeters that measure the energy of incident single photons by the resistance increase of a superconducting film biased within the superconducting-to-normal transition. TES are able to detect single photons from IR to X-ray with an intrinsic energy resolution and photon-number discrimination capability. Metrology, astronomy and quantum
communication are the fields where these properties can be particularly useful. In this work, we report about characterization of different TESs based on Ti films. Single photons have been detected from 200nm to 800 nm working at transition temperature Tc ∼ 100 mK. Using a pulsed laser at 690nm we have demonstrated the capability to resolve up to five photons
Towards joint reconstruction of noise and losses in quantum channels
The calibration of a quantum channel, i.e. the determination of the
transmission losses affecting it, is definitely one of the principal objectives
in both the quantum communication and quantum metrology frameworks. Another
task of the utmost relevance is the identification, e.g. by extracting its
photon number distribution, of the noise potentially present in the channel.
Here we present a protocol, based on the response of a photon-number-resolving
detector at different quantum efficiencies, able to accomplish both of these
tasks at once, providing with a single measurement an estimate of the
transmission losses as well as the photon statistics of the noise present in
the exploited quantum channel. We show and discuss the experimental results
obtained in the practical implementation of such protocol, with different kinds
and levels of noise.Comment: 6 pages, 4 figure
Self consistent, absolute calibration technique for photon number resolving detectors
Well characterized photon number resolving detectors are a requirement for
many applications ranging from quantum information and quantum metrology to the
foundations of quantum mechanics. This prompts the necessity for reliable
calibration techniques at the single photon level. In this paper we propose an
innovative absolute calibration technique for photon number resolving
detectors, using a pulsed heralded photon source based on parametric down
conversion. The technique, being absolute, does not require reference standards
and is independent upon the performances of the heralding detector. The method
provides the results of quantum efficiency for the heralded detector as a
function of detected photon numbers. Furthermore, we prove its validity by
performing the calibration of a Transition Edge Sensor based detector, a real
photon number resolving detector that has recently demonstrated its
effectiveness in various quantum information protocols.Comment: 9 pages, 2 figure
Quantum and classical characterization of single/few photon detectors
This paper's purpose is to review the results recently obtained in the
Quantum Optics labs of the National Institute of Metrological Research (INRIM)
in the field of single- and few-photon detectors calibration, from both the
classical and quantum viewpoint. In the first part of the paper is presented
the calibration of a single-photon detector with absolute methods, while in the
second part we focus on photon-number-resolving detectors, discussing both the
classical and quantum characterization of such devices.Comment: Quantum Matter in pres
Coherent Quantum Network of Superconducting Qubits as a Highly Sensitive Detector of Microwave Photons for Searching of Galactic Axions
We propose a novel approach to detect a low power microwave signal with a frequency of the order of several GHz based on a coherent collective response of quantum states occurring in a superconducting qubits network (SQN). An SQN composes of a large number of superconducting qubits embedded in a low-dissipative superconducting resonator. Our theory predicts that an SQN interacting with the off-resonance microwave radiation, demonstrates the collective alternating current Stark effect that can be measured even in the limit of single photon counting. A design of the layout of three terminals SQN detectors containing 10 flux qubits weakly coupled to a low-dissipative R-resonator and T-transmission line was developed. The samples were fabricated by Al-based technology with Nb resonator. The SQN detector was tested in terms of microwave measurements of scattering parameters and two-tone spectroscopy. A substantial shift of the frequency position of the transmission coefficient drop induced by a second tone pump signal was observed, and this effect clearly manifests a nonlinear multiphoton interaction between the second-tone microwave pump signal and an array of qubits
Progress in the development of a KITWPA for the DARTWARS project
DARTWARS (Detector Array Readout with Traveling Wave AmplifieRS) is a three
years project that aims to develop high-performing innovative Traveling Wave
Parametric Amplifiers (TWPAs) for low temperature detectors and qubit readout
(C-band). The practical development follows two different promising approaches,
one based on the Josephson junctions (TWJPA) and the other one based on the
kinetic inductance of a high-resistivity superconductor (KITWPA). This paper
presents the advancements made by the DARTWARS collaboration to produce a first
working prototype of a KITWPA.Comment: 3 pages, 4 figures. Proceeding of Pisa15th Meeting conferenc
Detector Array Readout with Traveling Wave Amplifiers
Reducing noise to the quantum limit over a large bandwidth is a fundamental requirement for future applications operating at millikelvin temperatures, such as the neutrino mass measurement, the next-generation X-ray observatory, the CMB measurement, the dark matter and axion detection, and the rapid high-fidelity readout of superconducting qubits. The read out sensitivity of arrays of microcalorimeter detectors, resonant axion-detectors, and qubits, is currently limited by the noise temperature and bandwidth of the cryogenic amplifers. The Detector Array Readout with Traveling Wave Amplifers project has the goal of developing high-performing innovative traveling wave parametric amplifers with a high gain, a high saturation power, and a quantum-limited or nearly quantum-limited noise. The practical development follows two diferent promising approaches, one based on the Josephson junctions and the other one based on the kinetic inductance of a high-resistivity superconductor. In this contribution, we present the aims of the project, the adopted design solutions and preliminary results from simulations and measurements
Bimodal Approach for Noise Figures of Merit Evaluation in Quantum-Limited Josephson Traveling Wave Parametric Amplifiers
The advent of ultra-low noise microwave amplifiers revolutionized several
research fields demanding quantum-limited technologies. Exploiting a
theoretical bimodal description of a linear phase-preserving amplifier, in this
contribution we analyze some of the intrinsic properties of a model
architecture (i.e., an rf-SQUID based Josephson Traveling Wave Parametric
Amplifier) in terms of amplification and noise generation for key case study
input states (Fock and coherents). Furthermore, we present an analysis of the
output signals generated by the parametric amplification mechanism when thermal
noise fluctuations feed the device.Comment: 5 pages, 6 figure
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