@inproceedings{10328,
abstract = {We discus noise channels in coherent electro-optic up-conversion between microwave and optical fields, in particular due to optical heating. We also report on a novel configuration, which promises to be flexible and highly efficient.},
author = {Lambert, Nicholas J. and Mobassem, Sonia and Rueda Sanchez, Alfredo R and Schwefel, Harald G.L.},
booktitle = {OSA Quantum 2.0 Conference},
isbn = {9-781-5575-2820-9},
location = {Washington, DC, United States},
publisher = {Optica Publishing Group},
title = {{New designs and noise channels in electro-optic microwave to optical up-conversion}},
doi = {10.1364/QUANTUM.2020.QTu8A.1},
year = {2020},
}
@article{7910,
abstract = {Quantum illumination uses entangled signal-idler photon pairs to boost the detection efficiency of low-reflectivity objects in environments with bright thermal noise. Its advantage is particularly evident at low signal powers, a promising feature for applications such as noninvasive biomedical scanning or low-power short-range radar. Here, we experimentally investigate the concept of quantum illumination at microwave frequencies. We generate entangled fields to illuminate a room-temperature object at a distance of 1 m in a free-space detection setup. We implement a digital phase-conjugate receiver based on linear quadrature measurements that outperforms a symmetric classical noise radar in the same conditions, despite the entanglement-breaking signal path. Starting from experimental data, we also simulate the case of perfect idler photon number detection, which results in a quantum advantage compared with the relative classical benchmark. Our results highlight the opportunities and challenges in the way toward a first room-temperature application of microwave quantum circuits.},
author = {Barzanjeh, Shabir and Pirandola, S. and Vitali, D and Fink, Johannes M},
issn = {2375-2548},
journal = {Science Advances},
number = {19},
publisher = {AAAS},
title = {{Microwave quantum illumination using a digital receiver}},
doi = {10.1126/sciadv.abb0451},
volume = {6},
year = {2020},
}
@article{8038,
abstract = {Microelectromechanical systems and integrated photonics provide the basis for many reliable and compact circuit elements in modern communication systems. Electro-opto-mechanical devices are currently one of the leading approaches to realize ultra-sensitive, low-loss transducers for an emerging quantum information technology. Here we present an on-chip microwave frequency converter based on a planar aluminum on silicon nitride platform that is compatible with slot-mode coupled photonic crystal cavities. We show efficient frequency conversion between two propagating microwave modes mediated by the radiation pressure interaction with a metalized dielectric nanobeam oscillator. We achieve bidirectional coherent conversion with a total device efficiency of up to ~60%, a dynamic range of 2 × 10^9 photons/s and an instantaneous bandwidth of up to 1.7 kHz. A high fidelity quantum state transfer would be possible if the drive dependent output noise of currently ~14 photons s^−1 Hz^−1 is further reduced. Such a silicon nitride based transducer is in situ reconfigurable and could be used for on-chip classical and quantum signal routing and filtering, both for microwave and hybrid microwave-optical applications.},
author = {Fink, Johannes M and Kalaee, M. and Norte, R. and Pitanti, A. and Painter, O.},
issn = {2058-9565},
journal = {Quantum Science and Technology},
number = {3},
publisher = {IOP Publishing},
title = {{Efficient microwave frequency conversion mediated by a photonics compatible silicon nitride nanobeam oscillator}},
doi = {10.1088/2058-9565/ab8dce},
volume = {5},
year = {2020},
}
@article{8944,
abstract = {Superconductor insulator transition in transverse magnetic field is studied in the highly disordered MoC film with the product of the Fermi momentum and the mean free path kF*l close to unity. Surprisingly, the Zeeman paramagnetic effects dominate over orbital coupling on both sides of the transition. In superconducting state it is evidenced by a high upper critical magnetic field 𝐵𝑐2, by its square root dependence on temperature, as well as by the Zeeman splitting of the quasiparticle density of states (DOS) measured by scanning tunneling microscopy. At 𝐵𝑐2 a logarithmic anomaly in DOS is observed. This anomaly is further enhanced in increasing magnetic field, which is explained by the Zeeman splitting of the Altshuler-Aronov DOS driving
the system into a more insulating or resistive state. Spin dependent Altshuler-Aronov correction is also needed to explain the transport behavior above 𝐵𝑐2.},
author = {Zemlicka, Martin and Kopčík, M. and Szabó, P. and Samuely, T. and Kačmarčík, J. and Neilinger, P. and Grajcar, M. and Samuely, P.},
issn = {2469-9969},
journal = {Physical Review B},
number = {18},
publisher = {American Physical Society},
title = {{Zeeman-driven superconductor-insulator transition in strongly disordered MoC films: Scanning tunneling microscopy and transport studies in a transverse magnetic field}},
doi = {10.1103/PhysRevB.102.180508},
volume = {102},
year = {2020},
}
@inproceedings{9001,
abstract = {Quantum illumination is a sensing technique that employs entangled signal-idler beams to improve the detection efficiency of low-reflectivity objects in environments with large thermal noise. The advantage over classical strategies is evident at low signal brightness, a feature which could make the protocol an ideal prototype for non-invasive scanning or low-power short-range radar. Here we experimentally investigate the concept of quantum illumination at microwave frequencies, by generating entangled fields using a Josephson parametric converter which are then amplified to illuminate a room-temperature object at a distance of 1 meter. Starting from experimental data, we simulate the case of perfect idler photon number detection, which results in a quantum advantage compared to the relative classical benchmark. Our results highlight the opportunities and challenges on the way towards a first room-temperature application of microwave quantum circuits.},
author = {Barzanjeh, Shabir and Pirandola, Stefano and Vitali, David and Fink, Johannes M},
booktitle = {IEEE National Radar Conference - Proceedings},
isbn = {9781728189420},
issn = {1097-5659},
location = {Florence, Italy},
number = {9},
publisher = {IEEE},
title = {{Microwave quantum illumination with a digital phase-conjugated receiver}},
doi = {10.1109/RadarConf2043947.2020.9266397},
volume = {2020},
year = {2020},
}
@article{9194,
abstract = {Quantum transduction, the process of converting quantum signals from one form of energy to another, is an important area of quantum science and technology. The present perspective article reviews quantum transduction between microwave and optical photons, an area that has recently seen a lot of activity and progress because of its relevance for connecting superconducting quantum processors over long distances, among other applications. Our review covers the leading approaches to achieving such transduction, with an emphasis on those based on atomic ensembles, opto-electro-mechanics, and electro-optics. We briefly discuss relevant metrics from the point of view of different applications, as well as challenges for the future.},
author = {Lauk, Nikolai and Sinclair, Neil and Barzanjeh, Shabir and Covey, Jacob P and Saffman, Mark and Spiropulu, Maria and Simon, Christoph},
issn = {2058-9565},
journal = {Quantum Science and Technology},
number = {2},
publisher = {IOP Publishing},
title = {{Perspectives on quantum transduction}},
doi = {10.1088/2058-9565/ab788a},
volume = {5},
year = {2020},
}
@article{9195,
abstract = {Quantum information technology based on solid state qubits has created much interest in converting quantum states from the microwave to the optical domain. Optical photons, unlike microwave photons, can be transmitted by fiber, making them suitable for long distance quantum communication. Moreover, the optical domain offers access to a large set of very well‐developed quantum optical tools, such as highly efficient single‐photon detectors and long‐lived quantum memories. For a high fidelity microwave to optical transducer, efficient conversion at single photon level and low added noise is needed. Currently, the most promising approaches to build such systems are based on second‐order nonlinear phenomena such as optomechanical and electro‐optic interactions. Alternative approaches, although not yet as efficient, include magneto‐optical coupling and schemes based on isolated quantum systems like atoms, ions, or quantum dots. Herein, the necessary theoretical foundations for the most important microwave‐to‐optical conversion experiments are provided, their implementations are described, and the current limitations and future prospects are discussed.},
author = {Lambert, Nicholas J. and Rueda Sanchez, Alfredo R and Sedlmeir, Florian and Schwefel, Harald G. L.},
issn = {2511-9044},
journal = {Advanced Quantum Technologies},
number = {1},
publisher = {Wiley},
title = {{Coherent conversion between microwave and optical photons - An overview of physical implementations}},
doi = {10.1002/qute.201900077},
volume = {3},
year = {2020},
}
@article{8755,
abstract = {The superconducting circuit community has recently discovered the promising potential of superinductors. These circuit elements have a characteristic impedance exceeding the resistance quantum RQ ≈ 6.45 kΩ which leads to a suppression of ground state charge fluctuations. Applications include the realization of hardware protected qubits for fault tolerant quantum computing, improved coupling to small dipole moment objects and defining a new quantum metrology standard for the ampere. In this work we refute the widespread notion that superinductors can only be implemented based on kinetic inductance, i.e. using disordered superconductors or Josephson junction arrays. We present modeling, fabrication and characterization of 104 planar aluminum coil resonators with a characteristic impedance up to 30.9 kΩ at 5.6 GHz and a capacitance down to ≤ 1 fF, with lowloss and a power handling reaching 108 intra-cavity photons. Geometric superinductors are free of uncontrolled tunneling events and offer high reproducibility, linearity and the ability to couple magnetically - properties that significantly broaden the scope of future quantum circuits. },
author = {Peruzzo, Matilda and Trioni, Andrea and Hassani, Farid and Zemlicka, Martin and Fink, Johannes M},
issn = {2331-7019},
journal = {Physical Review Applied},
number = {4},
publisher = {American Physical Society},
title = {{Surpassing the resistance quantum with a geometric superinductor}},
doi = {10.1103/PhysRevApplied.14.044055},
volume = {14},
year = {2020},
}
@article{8529,
abstract = {Practical quantum networks require low-loss and noise-resilient optical interconnects as well as non-Gaussian resources for entanglement distillation and distributed quantum computation. The latter could be provided by superconducting circuits but existing solutions to interface the microwave and optical domains lack either scalability or efficiency, and in most cases the conversion noise is not known. In this work we utilize the unique opportunities of silicon photonics, cavity optomechanics and superconducting circuits to demonstrate a fully integrated, coherent transducer interfacing the microwave X and the telecom S bands with a total (internal) bidirectional transduction efficiency of 1.2% (135%) at millikelvin temperatures. The coupling relies solely on the radiation pressure interaction mediated by the femtometer-scale motion of two silicon nanobeams reaching a Vπ as low as 16 μV for sub-nanowatt pump powers. Without the associated optomechanical gain, we achieve a total (internal) pure conversion efficiency of up to 0.019% (1.6%), relevant for future noise-free operation on this qubit-compatible platform.},
author = {Arnold, Georg M and Wulf, Matthias and Barzanjeh, Shabir and Redchenko, Elena and Rueda Sanchez, Alfredo R and Hease, William J and Hassani, Farid and Fink, Johannes M},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
publisher = {Springer Nature},
title = {{Converting microwave and telecom photons with a silicon photonic nanomechanical interface}},
doi = {10.1038/s41467-020-18269-z},
volume = {11},
year = {2020},
}
@article{9114,
abstract = {Microwave photonics lends the advantages of fiber optics to electronic sensing and communication systems. In contrast to nonlinear optics, electro-optic devices so far require classical modulation fields whose variance is dominated by electronic or thermal noise rather than quantum fluctuations. Here we demonstrate bidirectional single-sideband conversion of X band microwave to C band telecom light with a microwave mode occupancy as low as 0.025 ± 0.005 and an added output noise of less than or equal to 0.074 photons. This is facilitated by radiative cooling and a triply resonant ultra-low-loss transducer operating at millikelvin temperatures. The high bandwidth of 10.7 MHz and total (internal) photon conversion
efficiency of 0.03% (0.67%) combined with the extremely slow heating rate of 1.1 added output noise photons per second for the highest available pump power of 1.48 mW puts near-unity efficiency pulsed quantum transduction within reach. Together with the non-Gaussian resources of superconducting qubits this might provide the practical foundation to extend the range and scope of current quantum networks in analogy to electrical repeaters in classical fiber optic communication.},
author = {Hease, William J and Rueda Sanchez, Alfredo R and Sahu, Rishabh and Wulf, Matthias and Arnold, Georg M and Schwefel, Harald G.L. and Fink, Johannes M},
issn = {2691-3399},
journal = {PRX Quantum},
number = {2},
publisher = {American Physical Society},
title = {{Bidirectional electro-optic wavelength conversion in the quantum ground state}},
doi = {10.1103/prxquantum.1.020315},
volume = {1},
year = {2020},
}
@article{6053,
abstract = {Recent technical developments in the fields of quantum electromechanics and optomechanics have spawned nanoscale mechanical transducers with the sensitivity to measure mechanical displacements at the femtometre scale and the ability to convert electromagnetic signals at the single photon level. A key challenge in this field is obtaining strong coupling between motion and electromagnetic fields without adding additional decoherence. Here we present an electromechanical transducer that integrates a high-frequency (0.42 GHz) hypersonic phononic crystal with a superconducting microwave circuit. The use of a phononic bandgap crystal enables quantum-level transduction of hypersonic mechanical motion and concurrently eliminates decoherence caused by acoustic radiation. Devices with hypersonic mechanical frequencies provide a natural pathway for integration with Josephson junction quantum circuits, a leading quantum computing technology, and nanophotonic systems capable of optical networking and distributing quantum information.},
author = {Kalaee, Mahmoud and Mirhosseini, Mohammad and Dieterle, Paul B. and Peruzzo, Matilda and Fink, Johannes M and Painter, Oskar},
issn = {1748-3395},
journal = {Nature Nanotechnology},
number = {4},
pages = {334–339},
publisher = {Springer Nature},
title = {{Quantum electromechanics of a hypersonic crystal}},
doi = {10.1038/s41565-019-0377-2},
volume = {14},
year = {2019},
}
@article{6102,
abstract = {Light is a union of electric and magnetic fields, and nowhere is the complex relationship between these fields more evident than in the near fields of nanophotonic structures. There, complicated electric and magnetic fields varying over subwavelength scales are generally present, which results in photonic phenomena such as extraordinary optical momentum, superchiral fields, and a complex spatial evolution of optical singularities. An understanding of such phenomena requires nanoscale measurements of the complete optical field vector. Although the sensitivity of near- field scanning optical microscopy to the complete electromagnetic field was recently demonstrated, a separation of different components required a priori knowledge of the sample. Here, we introduce a robust algorithm that can disentangle all six electric and magnetic field components from a single near-field measurement without any numerical modeling of the structure. As examples, we unravel the fields of two prototypical nanophotonic structures: a photonic crystal waveguide and a plasmonic nanowire. These results pave the way for new studies of complex photonic phenomena at the nanoscale and for the design of structures that optimize their optical behavior.},
author = {Le Feber, B. and Sipe, J. E. and Wulf, Matthias and Kuipers, L. and Rotenberg, N.},
issn = {2047-7538},
journal = {Light: Science and Applications},
number = {1},
publisher = {Springer Nature},
title = {{A full vectorial mapping of nanophotonic light fields}},
doi = {10.1038/s41377-019-0124-3},
volume = {8},
year = {2019},
}
@article{6348,
abstract = {High-speed optical telecommunication is enabled by wavelength-division multiplexing, whereby hundreds of individually stabilized lasers encode information within a single-mode optical fibre. Higher bandwidths require higher total optical power, but the power sent into the fibre is limited by optical nonlinearities within the fibre, and energy consumption by the light sources starts to become a substantial cost factor1. Optical frequency combs have been suggested to remedy this problem by generating numerous discrete, equidistant laser lines within a monolithic device; however, at present their stability and coherence allow them to operate only within small parameter ranges2,3,4. Here we show that a broadband frequency comb realized through the electro-optic effect within a high-quality whispering-gallery-mode resonator can operate at low microwave and optical powers. Unlike the usual third-order Kerr nonlinear optical frequency combs, our combs rely on the second-order nonlinear effect, which is much more efficient. Our result uses a fixed microwave signal that is mixed with an optical-pump signal to generate a coherent frequency comb with a precisely determined carrier separation. The resonant enhancement enables us to work with microwave powers that are three orders of magnitude lower than those in commercially available devices. We emphasize the practical relevance of our results to high rates of data communication. To circumvent the limitations imposed by nonlinear effects in optical communication fibres, one has to solve two problems: to provide a compact and fully integrated, yet high-quality and coherent, frequency comb generator; and to calculate nonlinear signal propagation in real time5. We report a solution to the first problem.},
author = {Rueda Sanchez, Alfredo R and Sedlmeir, Florian and Kumari, Madhuri and Leuchs, Gerd and Schwefel, Harald G.L.},
issn = {1476-4687},
journal = {Nature},
number = {7752},
pages = {378--381},
publisher = {Springer Nature},
title = {{Resonant electro-optic frequency comb}},
doi = {10.1038/s41586-019-1110-x},
volume = {568},
year = {2019},
}
@inproceedings{7032,
abstract = {Optical frequency combs (OFCs) are light sources whose spectra consists of equally spaced frequency lines in the optical domain [1]. They have great potential for improving high-capacity data transfer, all-optical atomic clocks, spectroscopy, and high-precision measurements [2].},
author = {Rueda Sanchez, Alfredo R and Sedlmeir, Florian and Leuchs, Gerd and Kuamri, Madhuri and Schwefel, Harald G. L.},
booktitle = {2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference},
isbn = {9781728104690},
location = {Munich, Germany},
publisher = {IEEE},
title = {{Electro-optic frequency comb generation in lithium niobate whispering gallery mode resonators}},
doi = {10.1109/cleoe-eqec.2019.8873300},
year = {2019},
}
@article{7156,
abstract = {We propose an efficient microwave-photonic modulator as a resource for stationary entangled microwave-optical fields and develop the theory for deterministic entanglement generation and quantum state transfer in multi-resonant electro-optic systems. The device is based on a single crystal whispering gallery mode resonator integrated into a 3D-microwave cavity. The specific design relies on a new combination of thin-film technology and conventional machining that is optimized for the lowest dissipation rates in the microwave, optical, and mechanical domains. We extract important device properties from finite-element simulations and predict continuous variable entanglement generation rates on the order of a Mebit/s for optical pump powers of only a few tens of microwatts. We compare the quantum state transfer fidelities of coherent, squeezed, and non-Gaussian cat states for both teleportation and direct conversion protocols under realistic conditions. Combining the unique capabilities of circuit quantum electrodynamics with the resilience of fiber optic communication could facilitate long-distance solid-state qubit networks, new methods for quantum signal synthesis, quantum key distribution, and quantum enhanced detection, as well as more power-efficient classical sensing and modulation.},
author = {Rueda Sanchez, Alfredo R and Hease, William J and Barzanjeh, Shabir and Fink, Johannes M},
issn = {2056-6387},
journal = {npj Quantum Information},
publisher = {Springer Nature},
title = {{Electro-optic entanglement source for microwave to telecom quantum state transfer}},
doi = {10.1038/s41534-019-0220-5},
volume = {5},
year = {2019},
}
@inproceedings{7233,
abstract = {We demonstrate electro-optic frequency comb generation using a doubly resonant system comprising a whispering gallery mode disk resonator made of lithium niobate mounted inside a three dimensional copper cavity. We observe 180 sidebands centred at 1550 nm.},
author = {Rueda Sanchez, Alfredo R and Sedlmeir, Florian and Leuchs, Gerd and Kumari, Madhuri and Schwefel, Harald G.L.},
booktitle = {Nonlinear Optics, OSA Technical Digest},
isbn = {9781557528209},
location = {Waikoloa Beach, Hawaii (HI), United States},
publisher = {Optica Publishing Group},
title = {{Resonant electro-optic frequency comb generation in lithium niobate disk resonator inside a microwave cavity}},
doi = {10.1364/NLO.2019.NM2A.5},
year = {2019},
}
@article{7451,
abstract = {We prove that the observable telegraph signal accompanying the bistability in the photon-blockade-breakdown regime of the driven and lossy Jaynes–Cummings model is the finite-size precursor of what in the thermodynamic limit is a genuine first-order phase transition. We construct a finite-size scaling of the system parameters to a well-defined thermodynamic limit, in which the system remains the same microscopic system, but the telegraph signal becomes macroscopic both in its timescale and intensity. The existence of such a finite-size scaling completes and justifies the classification of the photon-blockade-breakdown effect as a first-order dissipative quantum phase transition.},
author = {Vukics, A. and Dombi, A. and Fink, Johannes M and Domokos, P.},
issn = {2521-327X},
journal = {Quantum},
publisher = {Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften},
title = {{Finite-size scaling of the photon-blockade breakdown dissipative quantum phase transition}},
doi = {10.22331/q-2019-06-03-150},
volume = {3},
year = {2019},
}
@article{6609,
abstract = {Mechanical systems facilitate the development of a hybrid quantum technology comprising electrical, optical, atomic and acoustic degrees of freedom1, and entanglement is essential to realize quantum-enabled devices. Continuous-variable entangled fields—known as Einstein–Podolsky–Rosen (EPR) states—are spatially separated two-mode squeezed states that can be used for quantum teleportation and quantum communication2. In the optical domain, EPR states are typically generated using nondegenerate optical amplifiers3, and at microwave frequencies Josephson circuits can serve as a nonlinear medium4,5,6. An outstanding goal is to deterministically generate and distribute entangled states with a mechanical oscillator, which requires a carefully arranged balance between excitation, cooling and dissipation in an ultralow noise environment. Here we observe stationary emission of path-entangled microwave radiation from a parametrically driven 30-micrometre-long silicon nanostring oscillator, squeezing the joint field operators of two thermal modes by 3.40 decibels below the vacuum level. The motion of this micromechanical system correlates up to 50 photons per second per hertz, giving rise to a quantum discord that is robust with respect to microwave noise7. Such generalized quantum correlations of separable states are important for quantum-enhanced detection8 and provide direct evidence of the non-classical nature of the mechanical oscillator without directly measuring its state9. This noninvasive measurement scheme allows to infer information about otherwise inaccessible objects, with potential implications for sensing, open-system dynamics and fundamental tests of quantum gravity. In the future, similar on-chip devices could be used to entangle subsystems on very different energy scales, such as microwave and optical photons.},
author = {Barzanjeh, Shabir and Redchenko, Elena and Peruzzo, Matilda and Wulf, Matthias and Lewis, Dylan and Arnold, Georg M and Fink, Johannes M},
journal = {Nature},
pages = {480--483},
publisher = {Nature Publishing Group},
title = {{Stationary entangled radiation from micromechanical motion}},
doi = {10.1038/s41586-019-1320-2},
volume = {570},
year = {2019},
}
@article{287,
abstract = {In this paper, we discuss biological effects of electromagnetic (EM) fields in the context of cancer biology. In particular, we review the nanomechanical properties of microtubules (MTs), the latter being one of the most successful targets for cancer therapy. We propose an investigation on the coupling of electromagnetic radiation to mechanical vibrations of MTs as an important basis for biological and medical applications. In our opinion, optomechanical methods can accurately monitor and control the mechanical properties of isolated MTs in a liquid environment. Consequently, studying nanomechanical properties of MTs may give useful information for future applications to diagnostic and therapeutic technologies involving non-invasive externally applied physical fields. For example, electromagnetic fields or high intensity ultrasound can be used therapeutically avoiding harmful side effects of chemotherapeutic agents or classical radiation therapy.},
author = {Salari, Vahid and Barzanjeh, Shabir and Cifra, Michal and Simon, Christoph and Scholkmann, Felix and Alirezaei, Zahra and Tuszynski, Jack},
journal = {Frontiers in Bioscience - Landmark},
number = {8},
pages = {1391 -- 1406},
publisher = {Frontiers in Bioscience},
title = {{Electromagnetic fields and optomechanics In cancer diagnostics and treatment}},
doi = {10.2741/4651},
volume = {23},
year = {2018},
}
@inproceedings{155,
abstract = {There is currently significant interest in operating devices in the quantum regime, where their behaviour cannot be explained through classical mechanics. Quantum states, including entangled states, are fragile and easily disturbed by excessive thermal noise. Here we address the question of whether it is possible to create non-reciprocal devices that encourage the flow of thermal noise towards or away from a particular quantum device in a network. Our work makes use of the cascaded systems formalism to answer this question in the affirmative, showing how a three-port device can be used as an effective thermal transistor, and illustrates how this formalism maps onto an experimentally-realisable optomechanical system. Our results pave the way to more resilient quantum devices and to the use of thermal noise as a resource.},
author = {Xuereb, André and Aquilina, Matteo and Barzanjeh, Shabir},
editor = {Andrews, D L and Ostendorf, A and Bain, A J and Nunzi, J M},
location = {Strasbourg, France},
publisher = {SPIE},
title = {{Routing thermal noise through quantum networks}},
doi = {10.1117/12.2309928},
volume = {10672},
year = {2018},
}