@article{10924,
abstract = {Solid-state microwave systems offer strong interactions for fast quantum logic and sensing but photons at telecom wavelength are the ideal choice for high-density low-loss quantum interconnects. A general-purpose interface that can make use of single photon effects requires < 1 input noise quanta, which has remained elusive due to either low efficiency or pump induced heating. Here we demonstrate coherent electro-optic modulation on nanosecond-timescales with only 0.16+0.02−0.01 microwave input noise photons with a total bidirectional transduction efficiency of 8.7% (or up to 15% with 0.41+0.02−0.02), as required for near-term heralded quantum network protocols. The use of short and high-power optical pump pulses also enables near-unity cooperativity of the electro-optic interaction leading to an internal pure conversion efficiency of up to 99.5%. Together with the low mode occupancy this provides evidence for electro-optic laser cooling and vacuum amplification as predicted a decade ago.},
author = {Sahu, Rishabh and Hease, William J and Rueda Sanchez, Alfredo R and Arnold, Georg M and Qiu, Liu and Fink, Johannes M},
issn = {20411723},
journal = {Nature Communications},
publisher = {Springer Nature},
title = {{Quantum-enabled operation of a microwave-optical interface}},
doi = {10.1038/s41467-022-28924-2},
volume = {13},
year = {2022},
}
@inproceedings{12088,
abstract = {We present a quantum-enabled microwave-telecom interface with bidirectional conversion efficiencies up to 15% and added input noise quanta as low as 0.16. Moreover, we observe evidence for electro-optic laser cooling and vacuum amplification.},
author = {Sahu, Rishabh and Hease, William J and Rueda Sanchez, Alfredo R and Arnold, Georg M and Qiu, Liu and Fink, Johannes M},
booktitle = {Conference on Lasers and Electro-Optics},
isbn = {9781557528209},
location = {San Jose, CA, United States},
publisher = {Optica Publishing Group},
title = {{Realizing a quantum-enabled interconnect between microwave and telecom light}},
doi = {10.1364/CLEO_QELS.2022.FW4D.4},
year = {2022},
}
@article{9242,
abstract = {In the recent years important experimental advances in resonant electro-optic modulators as high-efficiency sources for coherent frequency combs and as devices for quantum information transfer have been realized, where strong optical and microwave mode coupling were achieved. These features suggest electro-optic-based devices as candidates for entangled optical frequency comb sources. In the present work, I study the generation of entangled optical frequency combs in millimeter-sized resonant electro-optic modulators. These devices profit from the experimentally proven advantages such as nearly constant optical free spectral ranges over several gigahertz, and high optical and microwave quality factors. The generation of frequency multiplexed quantum channels with spectral bandwidth in the MHz range for conservative parameter values paves the way towards novel uses in long-distance hybrid quantum networks, quantum key distribution, enhanced optical metrology, and quantum computing.},
author = {Rueda Sanchez, Alfredo R},
issn = {2469-9934},
journal = {Physical Review A},
number = {2},
publisher = {American Physical Society},
title = {{Frequency-multiplexed hybrid optical entangled source based on the Pockels effect}},
doi = {10.1103/PhysRevA.103.023708},
volume = {103},
year = {2021},
}
@article{9815,
abstract = {The quantum bits (qubits) on which superconducting quantum computers are based have energy scales corresponding to photons with GHz frequencies. The energy of photons in the gigahertz domain is too low to allow transmission through the noisy room-temperature environment, where the signal would be lost in thermal noise. Optical photons, on the other hand, have much higher energies, and signals can be detected using highly efficient single-photon detectors. Transduction from microwave to optical frequencies is therefore a potential enabling technology for quantum devices. However, in such a device the optical pump can be a source of thermal noise and thus degrade the fidelity; the similarity of input microwave state to the output optical state. In order to investigate the magnitude of this effect we model the sub-Kelvin thermal behavior of an electro-optic transducer based on a lithium niobate whispering gallery mode resonator. We find that there is an optimum power level for a continuous pump, whilst pulsed operation of the pump increases the fidelity of the conversion.},
author = {Mobassem, Sonia and Lambert, Nicholas J. and Rueda Sanchez, Alfredo R and Fink, Johannes M and Leuchs, Gerd and Schwefel, Harald G.L.},
issn = {2058-9565},
journal = {Quantum Science and Technology},
number = {4},
publisher = {IOP Publishing},
title = {{Thermal noise in electro-optic devices at cryogenic temperatures}},
doi = {10.1088/2058-9565/ac0f36},
volume = {6},
year = {2021},
}
@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},
}
@inproceedings{15059,
abstract = {In this paper we present a room temperature radiometer that can eliminate the need of using cryostats in satellite payload reducing its weight and improving reliability. The proposed radiometer is based on an electro-optic upconverter that boosts up microwave photons energy by upconverting them into an optical domain what makes them immune to thermal noise even if operating at room temperature. The converter uses a high-quality factor whispering gallery
mode (WGM) resonator providing naturally narrow bandwidth and therefore might be useful for applications like microwave hyperspectral sensing. The upconversion process is explained by
providing essential information about photon conversion efficiency and sensitivity. To prove the concept, we describe an experiment which shows state-of-the-art photon conversion efficiency n=10-5 per mW of pump power at the frequency of 80 GHz.},
author = {Wasiak, Michal and Botello, Gabriel Santamaria and Abdalmalak, Kerlos Atia and Sedlmeir, Florian and Rueda Sanchez, Alfredo R and Segovia-Vargas, Daniel and Schwefel, Harald G. L. and Munoz, Luis Enrique Garcia},
booktitle = {14th European Conference on Antennas and Propagation},
location = {Copenhagen, Denmark},
publisher = {IEEE},
title = {{Compact millimeter and submillimeter-wave photonic radiometer for cubesats}},
doi = {10.23919/eucap48036.2020.9135962},
year = {2020},
}
@misc{13056,
abstract = {This datasets comprises all data shown in plots of the submitted article "Converting microwave and telecom photons with a silicon photonic nanomechanical interface". Additional raw data are available from the corresponding author on reasonable request.},
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},
publisher = {Zenodo},
title = {{Converting microwave and telecom photons with a silicon photonic nanomechanical interface}},
doi = {10.5281/ZENODO.3961561},
year = {2020},
}
@misc{13071,
abstract = {This dataset comprises all data shown in the plots of the main part of the submitted article "Bidirectional Electro-Optic Wavelength Conversion in the Quantum Ground State". Additional raw data are available from the corresponding author on reasonable request.},
author = {Hease, William J and Rueda Sanchez, Alfredo R and Sahu, Rishabh and Wulf, Matthias and Arnold, Georg M and Schwefel, Harald and Fink, Johannes M},
publisher = {Zenodo},
title = {{Bidirectional electro-optic wavelength conversion in the quantum ground state}},
doi = {10.5281/ZENODO.4266025},
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{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},
}
@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},
}
@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{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 = {14764687},
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},
}
@article{22,
abstract = {Conventional ultra-high sensitivity detectors in the millimeter-wave range are usually cooled as their own thermal noise at room temperature would mask the weak received radiation. The need for cryogenic systems increases the cost and complexity of the instruments, hindering the development of, among others, airborne and space applications. In this work, the nonlinear parametric upconversion of millimeter-wave radiation to the optical domain inside high-quality (Q) lithium niobate whispering-gallery mode (WGM) resonators is proposed for ultra-low noise detection. We experimentally demonstrate coherent upconversion of millimeter-wave signals to a 1550 nm telecom carrier, with a photon conversion efficiency surpassing the state-of-the-art by 2 orders of magnitude. Moreover, a theoretical model shows that the thermal equilibrium of counterpropagating WGMs is broken by overcoupling the millimeter-wave WGM, effectively cooling the upconverted mode and allowing ultra-low noise detection. By theoretically estimating the sensitivity of a correlation radiometer based on the presented scheme, it is found that room-temperature radiometers with better sensitivity than state-of-the-art high-electron-mobility transistor (HEMT)-based radiometers can be designed. This detection paradigm can be used to develop room-temperature instrumentation for radio astronomy, earth observation, planetary missions, and imaging systems.},
author = {Botello, Gabriel and Sedlmeir, Florian and Rueda Sanchez, Alfredo R and Abdalmalak, Kerlos and Brown, Elliott and Leuchs, Gerd and Preu, Sascha and Segovia Vargas, Daniel and Strekalov, Dmitry and Munoz, Luis and Schwefel, Harald},
issn = {23342536},
journal = {Optica},
number = {10},
pages = {1210 -- 1219},
title = {{Sensitivity limits of millimeter-wave photonic radiometers based on efficient electro-optic upconverters}},
doi = {10.1364/OPTICA.5.001210},
volume = {5},
year = {2018},
}
@inproceedings{485,
abstract = {We present results on nonlinear electro-optical conversion of microwave radiation into the optical telecommunication band with more than 0.1% photon number conversion efficiency with MHz bandwidth, in a crystalline whispering gallery mode resonator},
author = {Rueda Sanchez, Alfredo R and Sedlmeir, Florian and Collodo, Michele and Vogl, Ulrich and Stiller, Birgit and Schunk, Gerhard and Strekalov, Dmitry and Marquardt, Christoph and Fink, Johannes M and Painter, Oskar and Leuchs, Gerd and Schwefel, Harald},
booktitle = {Optics InfoBase Conference Papers},
isbn = {978-155752820-9},
location = {Waikoloa, HI, United States},
publisher = {Optica Publishing Group},
title = {{Single sideband microwave to optical photon conversion-an-electro-optic-realization}},
doi = {10.1364/NLO.2017.NM3A.1},
volume = {F54},
year = {2017},
}