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Title: All-optical digital logic: Full addition or subtraction on a three-state system

Abstract

Stimulated Raman adiabatic passage (STIRAP) is a well-studied pump-probe control scheme for manipulating the population of quantum states of atoms or molecules. By encoding the digits to be operated on as 'on' or 'off' laser input signals we show how STIRAP can be used to implement a finite-state logic machine. The physical conditions required for an effective STIRAP operation are related to the physical conditions expected for a logic machine. In particular, a condition is derived on the mean number of photons that represent an on pulse. A finite-state machine computes Boolean expressions that depend both on the input and on the present state of the machine. With two input signals we show how to implement a full adder where the carry-in digit is stored in the state of the machine. Furthermore, we show that it is possible to store the carry-out digit as the next state and thereby return the machine to a state ready for the next full addition. Such a machine operates as a cyclical full adder. We further show how this full adder can equally well be operated as a full subtractor. To the best of our knowledge this is the first example of a nanosizedmore » system that implements a full subtraction.« less

Authors:
;  [1];  [2]
  1. Departement de Chimie, B6c, Universite de Liege, B4000 Liege (Belgium)
  2. (Israel)
Publication Date:
OSTI Identifier:
20787000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.73.033820; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; ENERGY LEVELS; LASER RADIATION; LOGIC CIRCUITS; MOLECULES; NANOSTRUCTURES; OPTICS; PHOTONS; PULSES; QUANTUM COMPUTERS; SIGNALS

Citation Formats

Remacle, F., Levine, R. D., and Fritz Haber Research Center for Molecular Dynamics, Hebrew University of Jerusalem, Jerusalem 91904. All-optical digital logic: Full addition or subtraction on a three-state system. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Remacle, F., Levine, R. D., & Fritz Haber Research Center for Molecular Dynamics, Hebrew University of Jerusalem, Jerusalem 91904. All-optical digital logic: Full addition or subtraction on a three-state system. United States. doi:10.1103/PHYSREVA.73.0.
Remacle, F., Levine, R. D., and Fritz Haber Research Center for Molecular Dynamics, Hebrew University of Jerusalem, Jerusalem 91904. Wed . "All-optical digital logic: Full addition or subtraction on a three-state system". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787000,
title = {All-optical digital logic: Full addition or subtraction on a three-state system},
author = {Remacle, F. and Levine, R. D. and Fritz Haber Research Center for Molecular Dynamics, Hebrew University of Jerusalem, Jerusalem 91904},
abstractNote = {Stimulated Raman adiabatic passage (STIRAP) is a well-studied pump-probe control scheme for manipulating the population of quantum states of atoms or molecules. By encoding the digits to be operated on as 'on' or 'off' laser input signals we show how STIRAP can be used to implement a finite-state logic machine. The physical conditions required for an effective STIRAP operation are related to the physical conditions expected for a logic machine. In particular, a condition is derived on the mean number of photons that represent an on pulse. A finite-state machine computes Boolean expressions that depend both on the input and on the present state of the machine. With two input signals we show how to implement a full adder where the carry-in digit is stored in the state of the machine. Furthermore, we show that it is possible to store the carry-out digit as the next state and thereby return the machine to a state ready for the next full addition. Such a machine operates as a cyclical full adder. We further show how this full adder can equally well be operated as a full subtractor. To the best of our knowledge this is the first example of a nanosized system that implements a full subtraction.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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