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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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We present the possibilities to construct principal logic cell for reversible (adiabatic) computing by implementation of magnetic Josephson junction in usual dc-SQUID. The interest to this problem is motivated by extremely small energy dissipation per operation in the mentioned reversible SQUID-based logic circuits. The currently demonstrated specific energy dissipation per elementary operation for semiconductor technology is of the order of 106 kT, where k is the Boltzmann constant and T is the temperature. However, the thermodynamic threshold per logic operation, known as the Landauer limit, is equal to kT ln 2 [1, 2]. And this limit can be achieved and outperformed due to reversible controllable evolution of current states in arrays of magnetically coupled pi-shifted bi-SQUIDs. The suggested bi-SQUID is a two-junction interferometer, where geometric inductance is shunted with Josephson -junction in superconducting state. This shunt is based on a heterostructure with negative critical current, which consists of superconductor (S), insulator (I), and ferromagnetic (F), and normal (N) metal (e.g. SFS, SIsFS, SINFS et cetera). Fabrication and utilization of the suggested structure proved to be much more easier, then for the known Josephson reversible cells (based on SQUIDs with negative inductances and quantum parametron) [2, 3]. We start with the brief discussion of impact of magnetic Josephson junction on dc-SQUID potential energy. Then we present the analysis of reversible dynamics in single cell, in the cells, coupled in the transition line and in simple shift register. As a conclusion, we compare main characteristics (such as energy dissipation per operation and size) of the bi-SQUID-based adiabatic circuits with the same characteristics of the mentioned competing structures.