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1. High efficiency radio frequency antennas for amplifier free quantum sensing applications

   https://doi.org/10.1063/5.0136233  

   Mahtab, S.; Milas, P.; Veal, D.-T.; Spencer, M. G.; Ozturk, B. (April 2023, Review of Scientific Instruments)

   Radio frequency (RF) signals are frequently used in emerging quantum applications due to their spin state manipulation capability. Efficient coupling of RF signals into a particular quantum system requires the utilization of carefully designed and fabricated antennas. Nitrogen vacancy (NV) defects in diamond are commonly utilized platforms in quantum sensing experiments with the optically detected magnetic resonance (ODMR) method, where an RF antenna is an essential element. We report on the design and fabrication of high efficiency coplanar RF antennas for quantum sensing applications. Single and double ring coplanar RF antennas were designed with −37 dB experimental return loss at 2.87 GHz, the zero-field splitting frequency of the negatively charged NV defect in diamond. The efficiency of both antennas was demonstrated in magnetic field sensing experiments with NV color centers in diamond. An RF amplifier was not needed, and the 0 dB output of a standard RF signal generator was adequate to run the ODMR experiments due to the high efficiency of the RF antennas. 

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2. Molecular composition of comet 46P/Wirtanen from millimetre-wave spectroscopy

   https://doi.org/10.1051/0004-6361/202040125  

   Biver, N.; Bockelée-Morvan, D.; Boissier, J.; Moreno, R.; Crovisier, J.; Lis, D. C.; Colom, P.; Cordiner, M. A.; Milam, S. N.; Roth, N. X.; et al (April 2021, Astronomy & Astrophysics)

   null (Ed.)

   We present the results of a molecular survey of comet 46P/Wirtanen undertaken with the IRAM 30-m and NOEMA radio telescopes in December 2018. Observations at IRAM 30-m during the 12–18 December period comprise a 2 mm spectral survey covering 25 GHz and a 1 mm survey covering 62 GHz. The gas outflow velocity and kinetic temperature have been accurately constrained by the observations. We derive abundances of 11 molecules, some being identified remotely for the first time in a Jupiter-family comet, including complex organic molecules such as formamide, ethylene glycol, acetaldehyde, or ethanol. Sensitive upper limits on the abundances of 24 other molecules are obtained. The comet is found to be relatively rich in methanol (3.4% relative to water), but relatively depleted in CO, CS, HNC, HNCO, and HCOOH. 

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3. WIRELESS AND STAND-ALONE SUBMARINE PROPELLER BASED ON ACOUSTIC PROPULSION

   Lee, J; Kim, E.S. (June 2022, Hilton Head Workshop 2022: A Solid-State Sensors, Actuators and Microsystems Workshop)

   This paper presents a wireless and stand-alone subminiature propeller based on acoustic propulsion for the underwater robotic applications. The acoustic propulsion is generated by a MEMS-based self-focusing acoustic transducer (SFAT), fabricated on 1-mm-thick lead zirconate titanate (PZT) substrate, and operated at its thickness mode resonant frequency of 2.32 MHz. A 100F lithium-ion capacitor (LIC) is used as a power source due to its high energy and power densities. A drive electronic circuit is implemented on a flexible printed circuit board (PCB) and delivers 30Vpp sinusoidal signal to the acoustic propeller. The completed system is 18 x 18 x 38 mm3 in volume and weighs 12.56 grams, resulting in a mass density of 1.020 g/cm3. The acoustic propulsion generated by the acoustic propeller is measured to be 18.68μN with the electrical power of 358.7mW consumed by the propeller. Both vertical and horizontal propulsions are demonstrated successfully in sodium polytungstate (SPT) solution. 

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4. Coma composition of comet 67P/Churyumov-Gerasimenko from radio-wave spectroscopy

   https://doi.org/10.1051/0004-6361/202245672  

   Biver, N.; Bockelée-Morvan, D.; Crovisier, J.; Sandqvist, Aa.; Boissier, J.; Lis, D. C.; Cordiner, M.; Bonev, B. P.; Dello Russo, N.; Moreno, R.; et al (April 2023, Astronomy & Astrophysics)

   We present the results of a molecular survey of comet 67P/Churyumov-Gerasimenko undertaken with the Institut de RadioAstronomie Millimétrique (IRAM) 30-m radio telescope in November–December 2021, when it had its most favourable apparition in decades. Observations at IRAM 30-m during the 12–16 November period covered 8 GHz bandwidth at 3 mm, 16 GHz at 2 mm, and 60 GHz in the 1 mm window domain. These were completed by snapshots at 1 mm on 12–13 December and a short observation of the H 2 O line at 557 GHz with the Odin sub-millimetre observatory on 17.0 November 2021, and with 18-cm observations of OH with the Nançay radio telescope. Less sensitive observations obtained at a previous perihelion passage on 18–22 September 2015 with IRAM and 9–12 November 2015 with Odin are also presented. The gas outflow velocity, outgassing pattern, and temperature have been accurately constrained by the observations. They are perfectly consistent with those measured in situ with the Rosetta/MIRO sub-millimetre instrument in 2015. In particular, the asymmetry of the line is well represented by a jet concentrating three-quarters of the outgassing in about π steradians. We derived abundances relative to water for seven molecules and significant upper limits for approximately five others. The retrieved abundances were compared to those measured in situ at the previous perihelion with Rosetta. While those of HCN, CH 3 OH, and HNCO are comparable, 67P is found to be depleted in H 2 S and relatively normal in CS (H 2 S/CS ≈ 3) in strong contradiction with the Rosetta/ROSINA mass spectrometer measurement of the H 2 S/CS 2 (≈100) abundance ratio. While the formaldehyde total abundance found with IRAM 30-m when assuming it to be mostly produced by a distributed source (Haser parent scale length ≈8000 km) is similar to the one derived by Rosetta/ROSINA, we find that the formaldehyde coming from the nucleus is one order of magnitude less abundant than measured in situ by Rosetta/ROSINA. 

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5. Side-bounce beamlines using single-reflection diamond monochromators at Cornell High Energy Synchrotron Source

   https://doi.org/10.1107/S160057752100120X  

   Stoupin, Stanislav; Krawczyk, Thomas; Sagan, David; Temnykh, Alexander; Smieska, Louisa; Woll, Arthur; Ruff, Jacob; Lyndaker, Aaron; Pauling, Alan; Croom, Brendan P.; et al (March 2021, Journal of Synchrotron Radiation)

   The design and implementation of new beamlines featuring side-bounce (single-reflection) diamond monochromators at Cornell High Energy Synchrotron Source (CHESS) are described. Undulator radiation is monochromated using an interchangeable set of diamond crystal plates reflecting radiation in the horizontal (synchrotron) plane, where each crystal plate is set to one of the low-index Bragg reflections (111, 220, 311 and 400) in either Bragg or Laue reflection geometries. At the nominal Bragg angle of 18° these reflections deliver monochromated X-rays with photon energies of 9.7, 15.9, 18.65 and 22.5 keV, respectively. An X-ray mirror downstream of the diamond monochromator is used for rejection of higher radiation harmonics and for initial focusing of the monochromated beam. The characteristics of the X-ray beam entering the experimental station were measured experimentally and compared with the results of simulations. A reasonable agreement is demonstrated. It is shown that the use of selected high-dislocation-density `mosaic' diamond single-crystal plates produced using the chemical vapor deposition method yields a few-fold enhancement in the flux density of the monochromated beam in comparison with that delivered by perfect crystals under the same conditions. At present, the Functional Materials Beamline at CHESS, which is used for time-resolved in situ characterization of soft materials during processing, has been outfitted with the described setup. 

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