Nanoscale Electromagnetic Compatibility: Quantum Coupling and Matching in Nanocircuits

Abstract

Abstract-The paper investigates two typical electromagnetic compatibility (EMC) problems, namely, coupling and matching in nanoscale circuits composed of nano-interconnects and quantum devices in entangled state. Nano-interconnects under consideration are implemented by using carbon nanotubes or metallic nanowires, while quantum devices -by semiconductor quantum dots. Equivalent circuits of such nanocircuits contain additional elements arising at nanoscale due to quantum effects. As a result, the notions of coupling and impedance matching are reconsidered. Two examples are studied: in the first one, electromagnetically coupled nanowires are connected to classical lumped devices; in the second one, electromagnetically uncoupled transmission lines are terminated on quantum devices in entangled states. In both circuits the EMC features qualitatively and quantitatively differ from their classical analogs. In the second example, we demonstrate the existence of quantum coupling, due to the entanglement, which exists in spite of the absence of classical electromagnetic coupling. The entanglement also modifies the matching condition introducing a dependence of the optimal value of load impedance on the line length.Index Terms -Electromagnetic compatibility, kinetic inductance, nano-circuits, nano-electromagnetism, quantum devices, quantum entanglement. I. INTRODUCTIONODAY's achievements of nanoelectronics allow utilization and manipulation of small collections of atoms and molecules, such as semiconductor heterostructures, quantum wells, quantum wires and quantum dots [1][2][3] radiation with quantum mechanical low-dimensional systems.One of the crucial aspects of electromagnetism for electronic devices and systems is related to their electromagnetic compatibility, i.e., of their ability to operate successfully, with controlled levels of emissions and with a suitable degree of robustness to unwanted electromagnetic couplings via various mechanisms of interference [12][13][14].However, with the transition of electronics to nanoscale new physical phenomena as well as new materials' properties need to be studied. Quantum effects, such as: discrete energy spectrum of charge carriers, existence of phonons, ballistic transport and tunneling, many-body correlations, interface effects, and so on, manifest themselves jointly with classical electromagnetic interactions [15][16]. As a result, the classical design based on the phenomenological separate analysis of physical properties of electric circuit elements and functional properties of devices and systems becomes invalid with respect to nanoelectronics. These considerations lead to the conclusion that the "classical" EMC, completely based on macroscopic electrodynamics, must be deeply revised starting from the basic concepts and opening the era of "nanoEMC" [17][18][19].For instance, the classical scaling rules used to design integrated circuits (ICs) and to implement EMC solutions are based on the macroscopic behavior of the electrical parameters, such as inductances and capa...

Quantum Antennas

“…As it was shown in refs. [289, 298], the electric crosstalk becomes anomalously high even for rather weak mutual penetration of electromagnetic field. The manifestation of the entanglement can be strongly influenced by various elements of the environment (e.g., resonant cavities and waveguides near a cutoff).…”

Anomalous electromagnetic coupling via entanglement at the nanoscale

“…On the macroscale, the crosstalk noise between two circuit elements is a classical electromagnetic phenomenon, as a result of the EM-field penetration from one element into the other (and vice-versa). When the interaction is mainly due to the electric (magnetic) field penetration, the coupling is of capacitive (inductive) nature and is characterized by the effective mutual capacitances (inductances) [26][27][28]. At the nanoscale level, unusual crosstalk mechanisms may appear.…”

“…Thus, the negative resistance of a circuit element means that there is a special type of energy transfer inside the system, not supplied from outside. The appearance of negative resistance strongly contradicts the intuitive concepts of classical crosstalk, where the coupling channel of electromagnetic nature is represented by passive elements only [26][27][28].…”

“…The progress in nanoelectronics is accompanied by a general trend towards the application of radiocommunication principles to the optical frequency range, and thus intricate mechanisms of interference emerge on the nanoscale [26][27][28]. In fact, lumped electric circuits and segments of single-mode transmission lines became commonly used elements in high-frequency applications, including optical devices [29,30].…”

Quantum entanglement in electric circuits: From anomalous crosstalk to electromagnetic compatibility in nano-electronics

“…Consequently, in view of the quantum crosstalk the classical EMC concepts like coupling, shielding, and matching, were reconsidered with respect to nanodevices [8][9][10][11].…”