Theory of a quantum artificial neuron based on  superconducting devices

An artificial neuron using superconducting devices, so-called rf SQUID, working at the quantum-mechanical domain is studied. It is shown that quantum rf SQUID regarded as flux qubit can act as an artificial neuron with sigmoid function generated by coherent quantum-mechanical transitions between wells in double well potential representing rf SQUID.

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Theory of a superconducting artificial neuron for extended backpropagation learning algorism

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.29.18551 ◽

2018 ◽

Vol 7 (3.29) ◽

pp. 170

Author(s):

Haruna Katayama ◽

Toshiyuki Fujii ◽

Noriyuki Hatakenaka

Keyword(s):

Magnetic Fields ◽

Josephson Junctions ◽

Superconducting Devices ◽

Sigmoid Function ◽

Fixed Temperature ◽

Artificial Neuron ◽

Backpropagation Learning

An artificial neuron using superconducting devices, so-called double SQUID, applicable to the extended backpropagation learning algorism is studied. It is shown that the tunable slope of the sigmoid function required in the algorism can be achieved under the fixed temperature by externally applied magnetic fields threading the ring with two Josephson junctions in the double SQUID.

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INVESTIGATION COMPARISON ON THE GATE SPEED OF THREE-LEVEL AND TWO-LEVEL QUANTUM NOT GATES WITH ASYMMETRIC POTENTIAL OF rf-SQUID

Modern Physics Letters B ◽

10.1142/s0217984907013699 ◽

2007 ◽

Vol 21 (19) ◽

pp. 1261-1270 ◽

Cited By ~ 3

Author(s):

YING-HUA JI ◽

JU-JU HU ◽

SHI-HUA CAI

Keyword(s):

Microwave Pulse ◽

Diagonal Matrix ◽

Matrix Elements ◽

The Asymmetry ◽

Rf Squid ◽

Double Well Potential

We investigate the relation between the speed of quantum NOT gate and the asymmetry or detuning of the potential in system of the interaction of a two-level rf-SQUID qubit with a classical microwave pulse. The rf-SQUID is characterized by an asymmetric double well potential that gives rise to diagonal matrix elements. Then in resonance, we compare the gate speeds for three-level and two-level quantum NOT gates. We show that in general, a three-level gate is much faster than the conventional two-level gate.

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Improving the renormalization group approach to the quantum-mechanical double well potential

Physics Letters A ◽

10.1016/s0375-9601(01)00642-9 ◽

2001 ◽

Vol 290 (1-2) ◽

pp. 35-40 ◽

Cited By ~ 37

Author(s):

D. Zappalà

Keyword(s):

Renormalization Group ◽

Quantum Mechanical ◽

Group Approach ◽

Renormalization Group Approach ◽

Double Well Potential

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Magnetic reversal dynamics of a quantum system on a picosecond timescale

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.6.199 ◽

2015 ◽

Vol 6 ◽

pp. 1946-1956 ◽

Cited By ~ 12

Author(s):

Nikolay V Klenov ◽

Alexey V Kuznetsov ◽

Igor I Soloviev ◽

Sergey V Bakurskiy ◽

Olga V Tikhonova

Keyword(s):

Magnetic Moment ◽

Magnetization Reversal ◽

Quantum Mechanical ◽

Magnetic Reversal ◽

Level System ◽

Macroscopic Theory ◽

Atomic Systems ◽

Quantum Mechanical Description ◽

Classical Behavior ◽

Flux Qubit

We present our approach for a consistent, fully quantum mechanical description of the magnetization reversal process in natural and artificial atomic systems by means of short magnetic pulses. In terms of the simplest model of a two-level system with a magnetic moment, we analyze the possibility of a fast magnetization reversal on the picosecond timescale induced by oscillating or short unipolar magnetic pulses. We demonstrate the possibility of selective magnetization reversal of a superconducting flux qubit using a single flux quantum-based pulse and suggest a promising, rapid Λ-scheme for resonant implementation of this process. In addition, the magnetization reversal treatment is fulfilled within the framework of the macroscopic theory of the magnetic moment, which allows for the comparison and explanation of the quantum and classical behavior.

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