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Tunneling Diodes (tunneling + diode)
Selected AbstractsHybrid Nanoparticle/Organic Devices with Strong Resonant Tunneling BehaviorsADVANCED FUNCTIONAL MATERIALS, Issue 16 2009Tianhang Zheng Abstract A hybrid nanoparticle/organic device consisting of small molecule organic semiconductors and Ag nanoparticles is reported. The single device exhibits unusual properties of organic resonant tunneling diode (ORTD) at low driving voltage region and offers light emission at high voltage. For ORTD, a strong negative differential resistance behavior is demonstrated at room temperature. The current resonance with the peak-to-valley current ratio of over 4.6 and narrow linewidth of only ,1.4,V is achieved. A detailed operating mechanism of the charging and emission modes is proposed, which can be discussed in terms of the strong charge-trapping effect of Ag nanoparticles. The repeatable operations of hybrid device show the mutual influences between two modes and the light emission properties of the ORTD are also discussed. [source] Carbon nanotube , molecular resonant tunneling diodePHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 2 2006Rajeev R. Pandey Abstract Carbon nanotube (CNT) molecular resonant tunnel diodes (RTDs) are proposed to complement bio-assembled CNT field effect transistors (CNTFETs). A model CNT,pseudopeptide,CNT device is shown to exhibit the current,voltage response of an RTD. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Resonant Tunneling Processes along Conjugated Molecular Wires: A Quantum-Chemical DescriptionADVANCED FUNCTIONAL MATERIALS, Issue 11-12 2002Y. Karzazi Abstract Molecular electronics research is a very active area in the field of nanotechnology. It is now well established that individual or self-assembled molecules can behave as nanoscopic switches in transistor and diode configurations. Molecular wires inserted into nanopores and contacted by two metallic electrodes can also be used as active elements for the fabrication of resonant tunneling diodes (RTDs). The RTD current/voltage (I/V) characteristics can display a negative differential resistance (NDR) behavior (i.e., a negative slope in the I/V curve) for reasons that are not yet fully understood. Here we describe a possible mechanism at the quantum-chemical level that is based on conformational effects and accounts for the experimental observation of strong NDR signatures in substituted phenylene ethynylene oligomers. The occurrence of a peak current in the I/V curves is rationalized by analyzing the evolution of the one-electron structure of the molecular wires upon application of a static electric field aligned along the molecular axis (the field simulates the driving voltage applied between the two electrodes in the RTD devices). The results of our calculations provide a general basis to develop strategies for the design of molecular wires displaying an NDR behavior. [source] On circuit models for quantum-classical networks,INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 5-6 2007Árpád I. Csurgay Abstract Physics is not scale invariant, and today the scale of atoms and molecules challenges designers of machines in which quantum effects have dominant sway. What role could circuit theory play in designing machines described by quantum-classical models? Classical equivalent circuits do exist for systems composed of metal contacted and wired devices, such as resonant tunneling diodes, single electron transistors, metal,insulator,metal diodes, etc. circuits, but not for quantum-entangled networks, such as multi-quantum-state atoms. If devices were not contacted and wired by macroscopic metals, i.e. devices were classically field coupled, then generalized circuit models can be introduced. Case studies have been presented on the role of circuit models in quantum-classical systems. However, there are no ideal circuit elements capable of capturing the port properties of quantum-mechanical and/or quantum-optical subsystems and their coupling to classical waveguides or cavities. Copyright © 2007 John Wiley & Sons, Ltd. [source] A low local oscillator power K-band mixer based on tunneling diodesMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2009Iacopo Magrini Abstract In this article, we will demonstrate a low local oscillator (LO) power K-band mixer based on a tunneling diode technology. Due to its unique diode characteristics, no DC supply is needed, whereas an LO power as low as ,2 dBm is required for nominal functionality. The energy-efficient MMIC prototype integrates a pair of heterojunction interband tunnel diodes and a 90° coplanar broadband coupler. The prototype is optimized within the 19,26 GHz band, with an IF ranging from zero to 7 GHz. In addition, when compared with other mixers, it has the lowest LO power requirement with a conversion loss ranging from 6 to 10 dB, an input compression point of ,3 dBm and an intercept 2nd and 3rd order intermodulation point of 22 and 12 dBm, respectively. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1140,1143, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24228 [source] | ||||||||||