Showing papers by "Yoshihito Amemiya published in 1998"

Boltzmann machine neuron device using quantum-coupled single electrons

Abstract: A quantum Boltzmann machine (QBM) neuron device is proposed. It consists of a two-dimensional (2D) arrangement of quantum dots that is occupied by quantum-coupled single electrons. The two possible polarizations, “down” and “up,” of the electron spin are used to encode the binary states 0 and 1. The QBM neuron device produces stochastic operations naturally because the electron spin takes the polarization down or up with a certain probability. Calculations for the operation of the QBM neuron device are presented and it is demonstrated that the device can perform the stochastic operations of the BM neuron.

Quantum Cellular Automaton Device Using the Image Charge Effect

Abstract: A quantum cellular automaton (QCA) device that uses the image charge effect is proposed. This image-charge QCA device is constructed from many unit cells on a metal substrate covered with an insulator layer. Each unit cell consists of four quantum dots and two excess electrons. Two positive image charges in the metal substrate maintain the charge neutrality of each cell. The distance between two neighboring cells is designed to allow intercellular electron tunneling. The image-charge QCA cell can overcome two basic problems: establishing charge neutrality in each cell and loading electrons easily and precisely. We designed signal-transmission and elemental logic gate circuits using these image-charge QCA cells, and simulated operation of the circuits by computer simulation. It is demonstrated that the image-charge QCA circuits can perform signal transmission and elemental logic operations and that electrons (two per cell) can be easily loaded into the image-charge QCA circuits.

Circuit Systems Using Quantum-Effect Devices

Abstract: One of the goals in quantum electronics is to develop computing systems that can perform data processing by using quantum devices. There are two basic ways that we can use quantum-effect devices for data processing. One is to imitate existing silicon LSI circuit systems, using quantum devices as analogs of MOSFETs. The problem with this approach is that integrated circuits made of new transistor-type devices would have a hard time competing with silicon LSI, which is a well-established, mature technology. The more promising strategy is to reconsider the procedure for implementing data processing and to pursue a path different from that of ordinary LSI systems. This section reviews several approaches that are based on such a new-paradigm strategy.