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We consider theoretically an electronic Mach-Zehnder interferometer constructed from quantum Hall edge channels and quantum point contacts, fed with single electrons from a dynamic quantum dot source. By considering the energy dependence of the edge-channel guide centers, we give an account of the phase averaging in this setup that is particularly relevant for the short, high-energy wave packets injected by this type of electron source. We present both analytic and numerical results for the energy-dependent arrival time distributions of the electrons and also give an analysis of the delay times associated with the quantum point contacts and their effects on the interference patterns. A key finding is that, contrary to expectation, maximum visibility requires the interferometer arms to be different in length, with an offset of up to a micron for typical parameters. By designing interferometers that incorporate this asymmetry in their geometry, phase-averaging effects can be overcome such that visibility is only limited by other incoherent mechanisms. ; This research was supported by EPSRC Grant No. EP/P034012/1. S.R. was supported by the María de Maeztu Program for units of Excellence in R&D (Grant No. MDM-2017-0711). L.A.C. also acknowledges support from the Foundation for Polish Science within the "Quantum Optical Technologies" project carried out within the International Research Agendas programme cofinanced by the European Union under the European Regional Development Fund. H.S.S. was supported by the Korea NRF (SRC Center for Quantum Coherence in Condensed Matter, Grant No. 2016R1A5A1008184). M.K. was supported by the UK Department for Business, Energy, and Industrial Strategy, and by the European Metrology Programme for Innovation and Research (EMPIR). This project 17FUN04 SEQUOIA has received funding from the EMPIR programme cofinanced by the Participating States and from the European Union's Horizon 2020 research and innovation programme.

This experiment uses digital interferometry to reduce polarisation noise from a fiber interferometer to the level of double Rayleigh backscatter making precision fiber metrology systems robust for remote field applications. This is achieved with a measurement of the Jones matrix with interferometric sensitivity in real time, limited only by fibre length and processing bandwidth. This new approach leads to potentially new metrology applications and the ability to do ellipsometry without polarisation elements in the output field. ; This work was supported under the ARC DP grant number DP140103575 and the Australian Governments Australian Space Research Programme.

AbstractPhotonic chips have been recognized as a promising platform for information technology. On‐chip optical interferometers as fundamental building blocks of photonic chips are under extensive research with both conventional and novel fabrication techniques. Among them, recently, femtosecond laser has been attracting a great deal of attention as a powerful tool for directly writing micro‐optical devices in various materials due to its flexibility and three‐dimensional fabrication capability. This article gives a review on the working principles and recent achievements of on‐chip waveguides and interferometers fabricated by femtosecond laser, showing their potential applications in various scenarios.

[EN] Interferometers usually require long paths for the ever-increasing requirements of high-performance operation, which hinders the miniaturization and integration of photonic circuits into very compact devices. Slow-light based interferometers provide interesting advantages in terms of both compactness and sensitivity, although their optimization is computationally costly and inefficient, due to the large number of parameters to be simultaneously designed. Here we propose the design of slow-light-enhanced bimodal interferometers by using principal component analysis to reduce the high-dimensional design space. A low-dimensional hyperplane containing all optimized designs is provided and investigated for changes in the silicon core and cladding refractive index. As a result, all-dielectric single-channel interferometers as modulators of only 33 mu m(2) footprint and sensors with 19.2 x 10(3) 2 pi rad/RIU.cm sensitivity values are reported and validated by 2 different simulation methods. This work allows the design and optimization of slow light interferometers for different applications by considering several performance criteria, which can be extended to other photonic structures. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement ; European Commission (FEDER Valencia Regional Government 2014-2020); Spanish Government (PID2019-106965RBC21-PHOLOW); Generalitat Valenciana (ACIF/2019/009, AVANTI/2019/123, PPC/2020/037) ; Torrijos-Morán, L.; García-Rupérez, J. (2021). Design of slow-light-enhanced bimodal interferometers using dimensionality reduction techniques. Optics Express. 29(21):33962-33975. https://doi.org/10.1364/OE.425865 ; S ; 33962 ; 33975 ; 29 ; 21

"Union Carbide Corporation Nuclear Division operating the Oak Ridge Gaseous Diffusion Plant, Oak Ridge Y-12 Plant, Oak Ridge National Laboratory, and Paducah Gaseous Diffusion Plant for the Atomic Energy Commission under U.S. government contract W-7405-eng-26." ; Y-1466 ; "Contract W-7405-eng-26 with the US Atomic Energy Commission." ; "June 19, 1964; Date Issued: September 18, 1964 ; Report Number Y-1466 ; Instruments ; TID-4500 (32nd Edition)." ; Includes bibliographic references (p. 19). ; Mode of access: Internet.

We present measurement results for a laser frequency reference, implemented with an all-optical fiber Michelson interferometer, down to frequencies as low as 1 mHz. Optical fiber is attractive for space-based operations as it is physically robust, small and lightweight. The small free spectral range of fiber interferometers also provides the possibility to prestabilize two lasers on two distant spacecraft and ensures that the beatnote remains within the detector bandwidth. We demonstrate that these fiber interferometers are viable candidates for future laser-based gravity recovery and climate experiment missions requiring a stability of 30 Hz/√Hz over a 10 mHz-1 Hz bandwidth. ; This work was supported under the Australian Government's Australian Space Research Programme.

We present measurement results for a laser frequency reference, implemented with an all-optical fiber Michelson interferometer, down to frequencies as low as 1 mHz. Optical fiber is attractive for space-based operations as it is physically robust, small and lightweight. The small free spectral range of fiber interferometers also provides the possibility to prestabilize two lasers on two distant spacecraft and ensures that the beatnote remains within the detector bandwidth. We demonstrate that these fiber interferometers are viable candidates for future laser-based gravity recovery and climate experiment missions requiring a stability of 30 Hz/√Hz over a 10 mHz-1 Hz bandwidth. ; This work was supported under the Australian Government's Australian Space Research Programme.

In the present work, a multiwavelength fiber laser based in the combination of a double-random mirror and a suspended-core Sagnac interferometer is presented. The double-random mirror acts by itself as a random laser, presenting a 30dB SNR, as result of multiple Rayleigh scattering events produced in the dispersion compensating fibers by the Raman amplification. The suspended-core fiber Sagnac interferometer provides the multi peak channeled spectrum, which can be tuned by changing the length of the fiber. The result of this combination is a stable multiwavelength peak laser with a minimum of ~25dB SNR, which is highly sensitive to polarization induced variations. ; The authors are grateful to the Spanish Government project TEC2010-20224-C02-01 and to the European Cost Action TD-1001.