Article
Astronomy & Astrophysics
Marcin Hajduk, Marijke Haverkorn, Timothy Shimwell, Mateusz Olech, Joseph R. Callingham, Harish K. Vedantham, Glenn J. White, Marco Iacobelli, Alexander Drabent
Summary: Observations with LOFAR show thermal free-free emission from planetary nebulae shells, with determined electron temperatures lower than those estimated from optical emission lines. The existence of cold plasma component in coexistence with hot plasma is strongly supported, potentially affecting radio emission modeling of planetary nebulae.
ASTROPHYSICAL JOURNAL
(2021)
Article
Chemistry, Analytical
Si-jun Kim, Jang-jae Lee, Young-seok Lee, Chul-hee Cho, Shin-jae You
Summary: This paper proposes a novel method to measure the crossing frequency for high-pressure plasma diagnostics, expanding the operating range of the cutoff probe. The method is validated through electromagnetic wave simulation and experiments.
Article
Chemistry, Analytical
Si-Jun Kim, Min-Su Choi, Sang-Ho Lee, Won-Nyoung Jeong, Young-Seok Lee, In-Ho Seong, Chul-Hee Cho, Dae-Woong Kim, Shin-Jae You
Summary: This paper introduces a non-invasive microwave probe called the Tele-measurement of plasma Uniformity via Surface wave Information (TUSI) probe, which is of great importance for monitoring the electron density uniformity of plasma. By measuring the surface wave resonance frequency (S11) in a reflection microwave frequency spectrum, each antenna of the TUSI probe can estimate the electron density above it and provide an estimation of electron density uniformity. The results of the demonstration show that the TUSI probe can effectively monitor plasma uniformity and perform well when operated beneath a quartz or wafer. Therefore, the TUSI probe serves as a non-invasive in-situ method for measuring electron density uniformity.
Article
Instruments & Instrumentation
J. W. Brooks, E. M. Tejero, M. C. Palliwoda, M. S. McDonald
Summary: This work presents two advancements in plasma impedance probes (PIPs): a streamlined analytical model for interpreting PIP-monopole measurements and techniques for achieving =1 MHz time-resolved PIP measurements. The improved model includes measuring sheath thickness and provides a more accurate method for measuring electron density and damping. The time resolution is enhanced by using higher-frequency hardware, updated analysis algorithms, and a more rigorous approach to RF calibration.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Chemistry, Analytical
Si-jun Kim, Sang-ho Lee, Ye-bin You, Young-seok Lee, In-ho Seong, Chul-hee Cho, Jang-jae Lee, Shin-jae You
Summary: In this paper, the development of a microwave probe called MOLE is reported for measuring lateral electron density. Simulation and experimental results show that the MOLE probe is a useful instrument for monitoring electron density in materials.
Article
Chemistry, Analytical
Zhihao Zhao, Zheng Long, Huabei Wang, Qian Wu, Yang Wang, Hongmei Lu
Summary: In this study, a new integrated probe called pulled flowprobe was developed and compared with the previously reported single-probe for ambient liquid extraction-based mass spectrometry imaging (MSI). The results showed that the pulled flowprobe had higher extraction efficiencies and reduced band diffusion compared to the single-probe and other probes with a similar flow route. MSI using the pulled flowprobe detected higher signals of low-abundance lipids and more lipid species compared to the single-probe. The pulled flowprobe also demonstrated higher stability and spatial resolution, making it a promising tool for biological and clinical research.
ANALYTICAL CHEMISTRY
(2023)
Article
Optics
Bonan Liu, Shen Liu, Qiang Zhang, Guiqing Hong, Changrui Liao, Xizhen Xu, Liwei Liu, Junle Qu, Yiping Wang
Summary: A microbubble-probe whispering gallery mode resonator is proposed for displacement sensing with high resolution. The resonator consists of an air bubble and a probe with a diameter of about 5 μm, enabling micron-level spatial resolution. The fabricated resonator achieves a universal quality factor of over 106 through CO2 laser machining. It exhibits a displacement resolution of 74.83 pm and an estimated measurement span of 29.44 μm. As the first microbubble probe resonator for displacement measurement, it shows advantages in performance and demonstrates potential for high precision sensing.
Article
Instruments & Instrumentation
E. Naselli, R. Racz, S. Biri, M. Mazzaglia, A. Galata, L. Celona, S. Gammino, G. Torrisi, D. Mascali
Summary: In the context of the PANDORA_Gr3 project, a new multi-diagnostic approach has been proposed to correlate plasma parameters to nuclear activity. This approach involves several detectors and techniques, with a focus on high resolution spatially-resolved X-ray spectroscopy. By developing a new algorithm for analyzing single-photon-counted images, it has been possible to investigate the spatially resolved quantitative characterization of plasma versus plasma walls emitted spectra.
JOURNAL OF INSTRUMENTATION
(2022)
Article
Physics, Fluids & Plasmas
Mihai-Andrei Petrea, Eugen Stamate
Summary: This study utilized a dual thermal-electrostatic probe to reveal the spatial distribution of plasma parameters in aluminum-doped zinc oxide thin films deposited by magnetron plasma sputtering. The results showed a parabolic profile for plasma density and flat profiles for electron temperature and plasma potential, which were not correlated with the strong distribution of thin film resistivity.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Xiaofan Zhang, Xiaomeng Ma
Summary: We theoretically investigate the photoelectron momentum distributions of 1s and 2p(x, y) states of hydrogen by twisted attosecond X waves carrying orbital angular momentum based on first-order perturbation theory. The photoionization spectra as a function of photoelectron energy and emission angle are analyzed respectively. The results indicate that there are interference fringes in the energy spectra and more nodes in the angular distributions. These angular nodes are attributed to both orbital structure and the temporal-spatial structure of X waves. We derive an equation that can quantitatively describe the angular nodes in the photoelectron angular distributions. Our results and analyses indicate that the angular distribution is an important observation for the investigation of the information of both orbitals and X waves.
FRONTIERS IN PHYSICS
(2023)
Article
Astronomy & Astrophysics
S. P. Bos, K. L. Miller, J. Lozi, O. Guyon, D. S. Doelman, S. Vievard, A. Sahoo, V Deo, N. Jovanovic, F. Martinache, T. Currie, F. Snik
Summary: This study aims to demonstrate the on-sky effectiveness of spatial Linear Dark Field Control (LDFC) in mitigating the impact of quasi-static speckles on high-contrast imaging observations for exoplanet detection. By utilizing the science image as an additional wavefront sensor, LDFC successfully stabilizes the point spread function, enhancing the contrast in the high-contrast region.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Chemistry, Physical
Inho Seong, Si-jun Kim, Youngseok Lee, Chulhee Cho, Wonnyoung Jeong, Yebin You, Minsu Choi, Byeongyeop Choi, Shinjae You
Summary: Investigating the quenching of electron temperature in plasma processing is crucial for controlling electron temperature and improving the efficiency of plasma material processing.
Article
Chemistry, Physical
Chulhee Cho, Sijun Kim, Youngseok Lee, Inho Seong, Wonnyoung Jeong, Yebin You, Minsu Choi, Shinjae You
Summary: In this study, we investigated the voltages along the hot filament wire and emitting thermal electrons and proved which voltage reflects the plasma potential. This theoretical result was verified with a comparison of emissive probe measurements and Langmuir probe measurements in inductively coupled plasma. This work provides a significant contribution to the accurate measurement of plasma potential using the emissive probe with the floating potential method.
Article
Materials Science, Multidisciplinary
Jianwei Wang, Pingyang Wang, Li Peng
Summary: The enthalpy probe is a powerful tool in thermal plasma diagnostics due to its simplicity, reliability, and low cost. However, being an invasive measurement method, it affects the diagnostic process. This study investigates the impact factors such as probe presence and size, coolant and sampling-gas flow rates on thermal plasma diagnostics through experimental and simulation studies, and proposes an optimized measurement principle for the enthalpy probe.
Article
Chemistry, Analytical
Yoichi Otsuka, Bui Kamihoriuchi, Aya Takeuchi, Futoshi Iwata, Sara Tortorella, Takuya Matsumoto
Summary: Direct extraction and ionization techniques using minute amounts of solvent allow rapid analysis of chemical components in samples without sample preparation. A feedback control system applied to tapping-mode scanning probe electrospray ionization technique maintains probe vibration amplitude while scanning over uneven samples, enabling high-resolution imaging of molecular distribution and surface profiles. This method can be applied for examining multidimensional molecular distribution and surface profiles of various objects.
ANALYTICAL CHEMISTRY
(2021)
Article
Physics, Fluids & Plasmas
Shubo Li, Chengxun Yuan, Iya P. Kurlyandskaya, V. Demidov, M. E. Koepke, Jingfeng Yao, Zhongxiang Zhou
Summary: A single magnetically insulated baffled probe (MIBP) was used to study oscillations in a magnetized plasma. The study showed that the single MIBP can provide useful information about oscillation amplitudes, cross-coherency, and cross-phase. It also explained how to determine the maximum and minimum possible values of electron temperature fluctuations for cases with two types of oscillations.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Fluids & Plasmas
Hailu Wang, Jingfeng Yao, Aleksandr M. Astafiev, Anatoly A. Kudryavtsev, Chengxun Yuan, Zhongxiang Zhou, He-Ping Li
Summary: This study addresses the influence of an extended plasma jet on the radiation pattern of a short-grounded antenna in the frequency range of 1-3 GHz. Numerical and theoretical methods were used to determine the radiation pattern, and consistent results were obtained. A novel microwave diagnostic method for atmospheric plasma jets was also proposed based on the findings.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Shubo Li, Zhe Ding, Kurban M. Rabadanov, Anatoly A. Kudryavtsev, Nazir A. Ashurbekov, Jingfeng Yao, Chengxun Yuan, Zhongxiang Zhou
Summary: The formation of a nonlocal electron distribution function (EDF) in an argon dusty plasma of a dc glow discharge has been studied. The spatial profile of charges and the ambipolar potential can greatly vary with changes in the density and distribution of dust particles. This leads to strong differences in the nonlocal EDF at different points of the tube radius, especially at high dust particle densities.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Chengxun Yuan, Yan Chai, Eugene A. Bogdanov, Anatoly A. Kudryavtsev
Summary: This study investigates the influence of electron-electron collisions on the formation of inverse electron distribution function (EDF) and absolute negative conductivity (ANC) in a nonlocal plasma of a direct current glow discharge. A numerical model was built using COMSOL Multiphysics software and it includes kinetic equations for electrons, drift-diffusion fluid balance equations for heavy particles, and a Poisson equation for the electric field. The results show that the increase in electron-electron collisions limits the possibility of reverse EDF and ANC in rare gas nonlocal plasmas with Ramsauer minimum cross section.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Chengxun Yuan, Yan Chai, Eugene A. Bogdanov, Anatoly A. Kudryavtsev
Summary: It is demonstrated that the phenomenon of absolute negative electron mobility (ANG) has a subtle effect when considering the local plasma-chemical balance, and the sign of the electron mobility depends on the contribution of electronegative impurities.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Jianfei Li, Jingfeng Yao, Chengxun Yuan, Ying Wang, Zhongxiang Zhou, Jingwen Zhang, Anatoly A. Kudryavtsev
Summary: The inverse-brush-electrodes (IBE) structure is designed to investigate the discharge mechanism driven by alternating current (ac). It increases the number of secondary electrons and reduces the breakdown voltage compared to plate electrodes. The breakdown mechanism of gas discharge driven by ac is analyzed, and the negative differential conductivity enhancement effect of the IBE structure in heavy noble gas plasmas is studied. The effect is attributed to the non-equilibrium electron energy distribution function (EEDF) caused by the generation of suprathermal electrons by the IBE structure.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
Article
Physics, Fluids & Plasmas
N. A. Ashurbekov, M. Z. Zakaryaeva, K. M. Rabadanov, K. O. Iminov, M. B. Kurbangadzhieva, A. A. Kudryavtsev
Summary: This paper proposes a convenient method for calculating the electron energy distribution function (EEDF) in a gas-discharge plasma. The method is demonstrated by calculating the EEDF of a plasma column in a high-voltage nanosecond discharge in argon with an extended hollow cathode. The applicability of the method for calculating the EEDF in a pulsed discharge sustained by a 50 Hz pulse and gas pressure from 5 to 40 Torr is assessed.
PHYSICS OF PLASMAS
(2022)
Article
Physics, Fluids & Plasmas
Zijia Chu, Jingfeng Yao, Chengxun Yuan, Zhongxiang Zhou, Anatoly Kudryavtsev, Ying Wang, Xiaoou Wang
Summary: Laboratory plasmas, as highly nonlinear mediums, can exhibit various nonlinear phenomena. Hysteresis often occurs due to the coexistence of multiple attractors in nonlinear systems. In this study, a two-dimensional plasma fluid model is developed to investigate the hysteresis phenomenon in the nonlinear dynamical behaviors of low-pressure DC glow discharge. The results show that the selected initial discharge conditions significantly influence the exhibited nonlinear dynamical behaviors of the system.
PHYSICS OF PLASMAS
(2023)
Article
Physics, Fluids & Plasmas
Jingfeng Yao, Chai Yan, Chengxun Yuan, Eugene A. Bogdanov, Kurban Rabadanov, Zhijia Chu, Anatoly Kudryavtsev
Summary: This study presents self-consistent simulations of a glow discharge positive column in low-pressure nitrogen plasma. The electron energy distribution function (EEDF) was calculated by solving the nonlocal Boltzmann kinetic equation for electrons. The accuracy and applicability of the local and nonlocal approximations were examined. The results show that the nonlocal approximation is suitable at low nitrogen pressures, but a large intermediate region exists where the EEDF is nonlocal and requires solving the full kinetic equation. Therefore, the use of a local approximation in finding the EEDF should be carefully verified, especially at the periphery of the discharge volume where the self-consistent ambipolar field dominates.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Optics
Jianfei Li, Jingfeng Yao, Ying Wang, Zhongxiang Zhou, Anatoly. A. A. Kudryavtsev, Zhihao Lan, Chengxun Yuan
Summary: Traditional methods focus on mitigating electron densities and impurities around the antenna to alleviate plasma blackout, while metamaterial-based electromagnetic methods have yet to be proven experimentally. We simulate the plasma blackout problem using laboratory plasma supported by gas discharge technology. Topological edge states (TESs) that are insensitive to weak impurities in the transport path are verified theoretically and experimentally, providing a new approach to the blackout communication problem and serving as a nascent experimental platform to investigate topological electromagnetic phenomena.
Article
Physics, Fluids & Plasmas
Mohamed M. Mandour, Sergey A. Astashkevich, Anatoly A. Kudryavtsev
Summary: Photoplasma in Na-Ar mixtures in a two-chamber cell was studied to generate an electromotive force (EMF) with a wide range of buffer gas pressure. The Voigt profile of the D1 and D2 resonance lines of Na was investigated by considering radiation transfer within the framework of the Biberman-Holstein approximation. The obtained EMF was found to change its sign with buffer gas pressure variation due to the peculiarities of charge transport in the cell.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
Article
Physics, Fluids & Plasmas
Jingfeng Yao, Yan Chai, Chengxun Yuan, Eugene A. Bogdanov, Anatoly A. Kudryavtsev, Zhijia Chu, Ying Wang, Zhongxiang Zhou
Summary: This study analyzes the formation of the electron energy distribution function (EEDF) and phase flows of electrons in a positive column of a glow discharge in a model gas with strong vibrational excitation. It is found that the traditional local approximation for calculating the EEDF is only valid at medium gas pressures, and at lower gas pressures, the phase flow streamlines merge into a single line on the coordinate-energy phase plane. This merging is due to the combination of a strong electron sink at the vibrational excitation threshold and the deceleration of electrons in an ambipolar field.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Shixin Zhao, Xingbao Lyu, Yangguo Liu, Chengxun Yuan, Svetlana Avtaeva, Anatoly Kudryavtsev, Xiaoxue Li, Jingfeng Yao, Ying Wang, Zhongxiang Zhou
Summary: The characteristics of post-cathode plasma in a self-made DC short glow-discharge plasma generator with grid electrodes were measured using optical emission spectroscopy. The discharge operated in an abnormal glow discharge mode at a voltage of 250-400 V, a helium pressure of 3-15 Torr, and a discharge gap of 3 mm. The results showed that the intensity distribution of helium atom spectral lines differed between the post-cathode and post-anode spaces, and the temperature of electron excitation in the post-cathode plasma reached a peak of 1500-3000K at a distance of 5-6 mm from the grid cathode.
Article
Physics, Fluids & Plasmas
Zijia Chu, Jingfeng Yao, Chengxun Yuan, Zhongxiang Zhou, Anatoly Kudryavtsev, Xiaoou Wang, Ying Wang
Summary: This study investigates chaos phenomenon in the subnormal glow region of an undriven direct current glow discharge through the establishment of a two-dimensional plasma fluid model and coupling it with a circuit model. Various bifurcation processes are observed in the oscillation region, and the impact of control parameter on the spatiotemporal distribution of plasma parameters is examined. Additionally, the existence of periodic windows and intermittent chaos near the period-3 window is discovered.
Article
Computer Science, Information Systems
Xingbao Lyu, Chengxun Yuan, Svetlana Avtaeva, Anatoly Kudryavtsev, Jingfeng Yao, Yangguo Liu, Zhongxiang Zhou, Xiaoou Wang
Summary: This paper presents a new composite grid electrode structure, GA-CC, for generating plasma in atmospheric conditions. Compared to the ordinary grid anode-cathode plate (GA-CP) structure, the GA-CC structure has a lower breakdown voltage and is slightly shifted to the right on the Pd-axis. A notable advantage of the GA-CC structure is that it requires a lower voltage to generate the same current. Moreover, the plasma generated by the GA-CC structure selectively enhances electromagnetic wave attenuation within the frequency range of 9-12 GHz.