Article
Computer Science, Information Systems
Alina C. Bunea, Dan Neculoiu, Antonios Stavrinidis, George Stavrinidis, Athanasios Kostopoulos, George Konstantinidis
Summary: A W band communication link using monolithic integrated single-diode circuits is proposed, which includes GaAs Schottky diodes, folded slot antennas, and 3D printed dielectric lenses. This approach can serve as a low cost and low complexity alternative for point-to-point high-speed wireless communications.
Article
Engineering, Electrical & Electronic
M. Fregolent, M. Boito, A. Marcuzzi, C. De Santi, F. Chiocchetta, E. Bahat Treidel, M. Wolf, F. Brunner, O. Hilt, J. Wuerfl, G. Meneghesso, E. Zanoni, M. Meneghini
Summary: This paper reports on the isolation properties and failure mechanism of n-type vertical Pt / n-GaN Schottky barrier diodes and the dependence on the drift layer doping concentration. The results indicate that the Schottky barrier height is lower than expected, regardless of the doping density, limiting the blocking properties of the junction. The barrier lowering is associated with an injection mechanism involving deep levels in the semiconductor layer near the junction, facilitating carrier injection and tunneling. Furthermore, the failure of the devices in reverse bias condition is attributed to a power-related mechanism associated with current flowing along the mesa edges. Therefore, a good edge termination and passivation of the surfaces are essential for fully exploiting the blocking capability of the semiconductor.
MICROELECTRONICS RELIABILITY
(2022)
Article
Engineering, Electrical & Electronic
Ding Ding, Weiye Liu, Jiaping Guo, Xinhui Tan, Wei Zhang, Lili Han, Zhaowei Wang, Weihua Gong, Xiansheng Tang
Summary: According to classical theory, multi-quantum wells (MQWs) have been limited in their application in light-to-electric devices due to the quantum confinement effect on photo-generated carriers. However, experiments have shown that a significant proportion of carriers can escape from MQWs in the PIN structure, but not in the NIN structure. To study this phenomenon, we applied positive and negative bias to an NIN structure to simulate the PIN structure. Analysis of the photoluminescence spectra revealed a weak escape behavior of carriers in the NIN structure. The results suggest that a strong electric field can drive carriers to escape from MQWs, while the inhomogeneous distribution of electric field intensity in the NIN structure reduces carrier transport efficiency.
IEEE PHOTONICS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Shouqiang Lai, Chaohsu Lai, Saijun Li, Guolong Chen, Xi Zheng, Tingwei Lu, Zongming Lin, Rongxing Wu, Yijun Lu, Hao-Chung Kuo, Zhong Chen, Tingzhu Wu
Summary: In this study, the temperature-dependent photoluminescence characteristics of green InGaN/GaN multiple quantum wells (MQWs) with InGaN/GaN pre-wells and InGaN pre-layers were investigated, and the electroluminescence properties of the corresponding mini-LEDs were studied. The fitting results of the temperature-dependent photoluminescence spectra using the Vaishini and Arrhenius models showed that the S-shaped temperature-dependent peak energies of green InGaN/GaN MQWs grown on pre-wells and pre-layers originated from localized states, and better crystal quality was observed in the MQWs with pre-layers. Moreover, the electroluminescence properties of green mini-LEDs were compared, demonstrating the advantages of growing green MQWs with an InGaN prelayer.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Energy & Fuels
Yukun Sun, Shizhao Fan, Daehwan Jung, Ryan D. Hool, Brian Li, Michelle Vaisman, Minjoo Lee
Summary: This study shows that delta-doping significantly improves the performance of tunnel junctions used as interconnects in III-V multijunction solar cells. Delta-doping performs even better in tunnel junctions based on wider-bandgap materials with reduced optical absorption. Importantly, delta-doped tunnel junctions can withstand the thermal loads encountered during the growth of additional subcells.
IEEE JOURNAL OF PHOTOVOLTAICS
(2022)
Article
Engineering, Electrical & Electronic
Prakash Pandey, Tolen M. Nelson, William M. Collings, Michael R. Hontz, Daniel G. Georgiev, Andrew D. Koehler, Travis J. Anderson, James C. Gallagher, Geoffrey M. Foster, Alan Jacobs, Mona A. Ebrish, Brendan P. Gunning, Robert J. Kaplar, Karl D. Hobart, Raghav Khanna
Summary: A simple edge termination structure for a GaN p-n diode is proposed, which has been empirically validated to increase breakdown capability. This technique reduces complexity in manufacturing and improves the device's voltage-blocking ability.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Xuan Liu, Maojun Wang, Jin Wei, Cheng P. Wen, Bing Xie, Yilong Hao, Xuelin Yang, Bo Shen
Summary: Utilizing hydrogen plasma treatment and controlled diffusion, a junction termination extension (JTE) structure with gradient hole density (GHD) is spontaneously formed for vertical gallium nitride (GaN) p-n diode based on selective area partial passivation of Mg acceptors with hydrogen. The reverse bias for the quasi-vertical GaN-on-Si p-n diodes to reach a leakage current of 1 A/cm(2) was boosted from 631 to 1100 V. Additionally, the fabricated diode exhibited superior rectifying behavior with an ON/OFF-current ratio of 10(12) and a specific differential ON-resistance of 0.75 m omega middot cm(2).
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Multidisciplinary
A. Rozhkov
Summary: This article demonstrates the potential of using high-voltage GaAs drift step-recovery diodes to generate subnanosecond pulses, with a described circuit capable of producing high-amplitude pulses with fast rise time and short width at a load of 50 ohms, achieving an efficiency of at least 25%.
INSTRUMENTS AND EXPERIMENTAL TECHNIQUES
(2021)
Article
Crystallography
J. Iwan Davies, Andrew D. Johnson, Rodney I. Pelzel, Matthew D. Geen, Andrew M. Joel, Sung Wook Lim
Summary: III-V Compound Semiconductors, such as GaAs, InP, and GaN, are critical in supporting major technological revolutions and have high potential in the growing photonics industry. The mass-manufacturing of VCSEL-based devices, with improvements in cost-reduction and uniformity, is crucial in driving market growth in areas like 3D imaging, sensing, LIDAR applications, datacom, and industrial markets. The scalability to larger wafer diameters and in-situ process control are key challenges that need to be addressed for successful mass-production.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Engineering, Electrical & Electronic
Hedieh Mahmoodnia, Alireza Salehi, Valmor Roberto Mastelaro
Summary: The enhancement of gas sensing characteristics of GaAs-based Schottky diode sensors passivated by ammonium sulfide solution has been demonstrated in this work, with the response time significantly reduced upon exposure to ammonia gas. The passivated diode exhibits improved electrical characteristics and response rate, attributed to the reduction of metal-semiconductor interface states and prevention of Fermi level pinning.
IEEE SENSORS JOURNAL
(2021)
Article
Acoustics
Meng-Yu Tsai, Szu-Yu Pan, Jian-Jang Huang
Summary: Researchers have developed a radio frequency-modulated light emitter driven by the coupling between electrical and acoustic signals at room temperature, which exhibits a 990MHz oscillation behavior that cannot be solely achieved by electrical driving. This phenomenon is attributed to the excitation by the harmonics of surface acoustic waves in the light emitter.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2021)
Article
Engineering, Electrical & Electronic
Shifeng Li, Lijun Ma, Leiyang Wang, Xiao Lei, Bang Wu, Gary J. Cheng, Feng Liu
Summary: A high-power wideband monolithic limiter was successfully realized by using GaAs p-i-n process based on a rounded rectangle p-i-n diode with the minimum radius allowed by the process and a 0.8-mu m thick I-layer. The monolithic limiter can handle a maximum power of 400 W (56dBm) at 16 GHz, while the output power is less than 45 mW (16.5 dBm). The limiter has an insertion loss of less than 0.55 dB and a return loss better than -15 dB in the frequency range of 10-18 GHz, which has minimal impact on the receiver signal.
IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Feng Zhou, Weizong Xu, Fangfang Ren, Dong Zhou, Dunjun Chen, Rong Zhang, Youdou Zheng, Tinggang Zhu, Hai Lu
Summary: A quasi-vertical GaN junction barrier Schottky diode on low-cost sapphire substrate was successfully demonstrated, exhibiting excellent performance attributes such as low reverse leakage, high breakdown voltage, and fast switching capability. Improved heat dissipation techniques enable the diode to achieve high current rectification levels, high power efficiency, and low case temperatures.
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Crystallography
D. Lackner, T. Urban, R. Lang, C. Pellegrino, J. Ohlmann, V. Dudek
Summary: Schottky diodes designed with GaAs can be used in power supplies, motor drives, battery charging, and server/data centers. These diodes have high electron mobilities and lower power consumption compared to Si, GaN, and SiC diodes. A low-cost and ultrafast growth process using MOVPE has been developed for Schottky power diodes.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Engineering, Electrical & Electronic
Ioannis E. Fragkos, Wei Sun, Damir Borovac, Renbo Song, Jonathan J. Wierer, Nelson Tansu
Summary: This study investigates an active region design based on InGaN / delta-InN quantum well (QW) for potential high-efficiency visible light emitters. The results demonstrate a large wavelength redshift and an increase in the electron-hole wavefunction overlap for the delta-structure compared to the conventional InGaN QW.
IEEE JOURNAL OF QUANTUM ELECTRONICS
(2022)
Article
Physics, Applied
C. Puglia, G. De Simoni, F. Giazotto
Summary: The effect of electrostatic gating on metallic elemental superconductors was demonstrated in terms of modulation of the switching current and control of the current phase relation. The measurement of the switching current cumulative probability distributions is a useful tool to analyze the gating effect. This paper summarizes the main results obtained in the analysis of phase slip events in elemental gated superconducting weak-links.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Biotechnology & Applied Microbiology
Margherita Montorsi, Giada G. Genchi, Daniele De Pasquale, Giorgio De Simoni, Edoardo Sinibaldi, Gianni Ciofani
Summary: Traditional bone tissue engineering has used various types of bioreactors to study osteogenic differentiation, but single-mode bioreactors often fail to mimic physiological conditions effectively. This study developed a multi-modal perfusion bioreactor that induced differentiation of SaOS-2 bone-derived cells and achieved a faster bone matrix deposition rate.
BIOTECHNOLOGY AND BIOENGINEERING
(2022)
Article
Chemistry, Physical
Valentina Zannier, Ang Li, Francesca Rossi, Sachin Yadav, Karl Petersson, Lucia Sorba
Summary: In order to use III-V compound semiconductors as active channel materials in advanced electronic and quantum devices, it is important to achieve a good epitaxial growth on silicon substrates. The study reports on the selective-area growth of GaP/InGaP/InP/InAsP buffer layer nanotemplates on GaP substrates which are closely lattice-matched to silicon, suitable for the integration of in-plane InAs nanowires. The results demonstrate that a growth sequence of thin layers with progressively increasing lattice parameters is effective to efficiently relax the strain and eventually obtain high quality in-plane InAs nanowires on large lattice-mismatched substrates.
Article
Chemistry, Multidisciplinary
Isha Verma, Valentina Zannier, Vladimir G. Dubrovskii, Fabio Beltram, Lucia Sorba
Summary: In this study, InSb nanoflags were grown on Au-catalyzed InP nanowires using chemical beam epitaxy, forming regular arrays on patterned substrates. The evolution of nanoflag dimensions with growth time was investigated, and a model was proposed to explain the observed nonlinear time dependence of nanoflag length and width increase.
Article
Physics, Multidisciplinary
M. Knorr, J. M. Manceau, J. Mornhinweg, J. Nespolo, G. Biasiol, N. L. Tran, M. Malerba, P. Goulain, X. Lafosse, M. Jeannin, M. Stefinger, I Carusotto, C. Lange, R. Colombelli, R. Huber
Summary: The ultrafast scattering dynamics of intersubband polaritons in dispersive cavities embedding GaAs/AlGaAs quantum wells were directly studied using a noncollinear pump-probe geometry with phase-stable midinfrared pulses. Selective excitation of the lower polariton at a frequency of similar to 25 THz and at a finite in-plane momentum k(parallel to) resulted in the emergence of a narrowband maximum in the probe reflectivity at k(parallel to) = 0. A quantum mechanical model identified the underlying microscopic process as stimulated coherent polariton-polariton scattering.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Analytical
Matija Colja, Marco Cautero, Ralf Hendrik Menk, Pierpaolo Palestri, Alessandra Gianoncelli, Matias Antonelli, Giorgio Biasiol, Simone Dal Zilio, Tereza Steinhartova, Camilla Nichetti, Fulvia Arfelli, Dario De Angelis, Francesco Driussi, Valentina Bonanni, Alessandro Pilotto, Gianluca Gariani, Sergio Carrato, Giuseppe Cautero
Summary: In this article, the advantages of III-V compound semiconductors and dedicated alloys over Si-based technologies in hard X-ray applications are discussed, with a focus on gallium arsenide (GaAs) as a valuable material. The experimental characterizations of GaAs avalanche photodiodes (APDs) with different thicknesses of the absorption regions are described, highlighting the role of thickness in charge collection efficiency and the potential for using APDs without reaching the punch-through voltage.
Article
Physics, Applied
Giorgio De Simoni, Nadia Ligato, Francesco Giazotto, Lorenzo Cassola, Giuseppe C. Tettamanzi
Summary: This paper reports an aluminum double-loop bi-SQUID based on proximitized mesoscopic copper Josephson junctions, which is important for quantum sensing and signal processing in the radio-frequency range. The new fabrication approach allows for adjustable junction characteristics and device responses through the geometry of the metallic weak links, which is different from conventional tunnel-junction-based interferometers.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Applied
F. Paolucci, G. De Simoni, F. Giazotto
Summary: We have designed and fabricated a monolithic device that demonstrates a valuable non-reciprocal charge transport effect by utilizing a Dayem bridge-based superconducting quantum interference device. Our structure achieves rectification efficiencies (eta) up to similar to 6%. Furthermore, the absolute value and the polarity of g can be selectively modulated by an external magnetic flux or a gate voltage, offering high versatility and improved switching speed. In addition, our device operates in a wide temperature range, up to about 70% of the superconducting critical temperature of the titanium film. Our non-reciprocal charge transport effect holds great potential for extended applications in superconducting electronics, synergizing with widespread superconducting technologies such as nanocryotrons, rapid single flux quanta, and memories.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Omer Arif, Valentina Zannier, Francesca Rossi, Diego De Matteis, Katharina Kress, Marta De Luca, Ilaria Zardo, Lucia Sorba
Summary: Nanowire geometry offers the possibility of obtaining semiconductor heterostructures that are not achievable in planar systems, allowing for the exploration of new optical transitions and vibrational properties. High-quality superlattice nanowires have shown improved thermoelectric properties and the potential for engineering photonic and phononic properties at the nanoscale.
Article
Multidisciplinary Sciences
Arunav Bordoloi, Valentina Zannier, Lucia Sorba, Christian Schoenenberger, Andreas Baumgartner
Summary: Correlations are fundamental to many-body systems, but are notoriously difficult to assess experimentally on a microscopic scale. This study reports the direct measurement of spin cross-correlations between currents in a Cooper pair splitter. Using ferromagnetic split-gates to individually spin polarize the transmissions of quantum dots, the study finds negative spin cross-correlations consistent with spin singlet emission.
Article
Chemistry, Multidisciplinary
Samuele Cornia, Valeria Demontis, Valentina Zannier, Lucia Sorba, Alberto Ghirri, Francesco Rossella, Marco Affronte
Summary: Novel approaches exploiting the interaction between microwaves and quantum devices are being developed for efficient microwave detection. In this study, InAs/InP nanowire double quantum dot-based devices are used as nanoscale detectors to measure the local field without calibration. The detector performance is evaluated, and it is shown that these devices allow direct assessment of the microwave field with high sensitivity and spatial resolution, potentially advancing the development of high-performance microwave circuitries.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Mathieu Jeannin, Eduardo Cosentino, Stefano Pirotta, Mario Malerba, Giorgio Biasiol, Jean-Michel Manceau, Raffaele Colombelli
Summary: We demonstrate that absorption saturation of a mid-infrared intersubband transition can be achieved at moderate light intensities, showing potential for practical applications. The structure consists of a specially designed semiconductor heterostructure deposited on metal patches. By varying the incident intensity, the structure can switch from strong light-matter coupling with two absorption peaks to weak coupling with a single-peaked absorption. The behavior of the system can be explained using a coupled mode theory model, providing insights into the relevant system parameters.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Giorgio De Simoni, Francesco Giazotto
Summary: Superconducting interferometers, such as the bi-SQUIPT proposed in this study, offer a linear flux-to-voltage mesoscopic transducer with excellent sensitivity and dynamic range. It provides a low voltage-noise spectral density and is tolerant to imperfections and nonidealities. This has significant implications for low-dissipation and low-noise current amplification in cryogenic quantum electronics applications.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
A. Iorio, A. Crippa, B. Turini, S. Salimian, M. Carrega, L. Chirolli, V. Zannier, L. Sorba, E. Strambini, F. Giazotto, S. Heun
Summary: In this study, a ballistic InSb nanoflag-based Josephson junction with Nb superconducting contacts is investigated. The high transparency of the superconductor-semiconductor interfaces allows for the exploration of quantum transport with short and long conducting channels. Half-integer Shapiro steps are observed under microwave irradiation, which are robust to temperature and suggest a possible nonequilibrium origin. The results demonstrate the potential of ballistic InSb nanoflags Josephson junctions as a valuable platform for understanding the physics of hybrid devices and investigating their nonequilibrium dynamics.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Mate Suto, Tamas Prok, Peter Makk, Magdhi Kirti, Giorgio Biasiol, Szabolcs Csonka, Endre Tovari
Summary: We studied a near-surface two-dimensional electron gas based on an InAs quantum well on a GaAs substrate. High electron mobilities were estimated in devices without a dielectric layer. We observed quantized conductance in a quantum point contact and determined the g factor. Multiple Josephson junctions were defined using samples with an epitaxial Al layer, and the critical current was found to be gate tunable. The semiconductor-superconductor interface was transparent based on multiple Andreev reflections, with an induced gap of 125 mu eV. Our results suggest that this InAs system is a viable platform for use in hybrid topological superconductor devices.
