Showing papers on "Open quantum system published in 1983"
Book•
01 Jan 1983
1,294 citations
01 Jan 1983
TL;DR: In this paper, it was shown that molecules with a quantum-theoretical distribution of states in thermal equilibrium, were in dynamical equilibrium with the Planck radiation; in this way, Planck's formula (4) could be derived in an astonishingly simple and general way.
Abstract: on the assumption of discrete portions of energy, from which quantum theory developed rapidly. It was then only natural that Wien’s argument, which had led to eq. (2), should have become forgotten. Not long ago I discovered a derivation of Planck’s formula which was closely related to Wien’s original argument 1 and which was based on the fundamental assumption of quantum theory. This derivation displays the relationship between Maxwell’s curve and the chromatic distribution curve and deserves attention not only because of its simplicity, but especially because it seems to throw some light on the mechanism of emission and absorption of radiation by matter, a process which is still obscure to us. By postulating some hypotheses on the emission and absorption of radiation by molecules, which suggested themselves from quantum theory, I was able to show that molecules with a quantum-theoretical distribution of states in thermal equilibrium, were in dynamical equilibrium with the Planck radiation; in this way, Planck’s formula (4) could be derived in an astonishingly simple and general way. It was obtained from the condition that the internal energy distribution of the molecules demanded by quantum theory, should follow purely from an emission and absorption of radiation. But if these hypotheses on the interaction between radiation and matter turn out to be justified, they must produce rather more than just the correct statistical distribution of the internal energy of the molecules: for
846 citations
Book•
31 Jul 1983
657 citations
IBM1
TL;DR: In this paper, the eigenstate of an isolated quantum well subject to an external electric field was analyzed and a quadratic Stark shift was found whose magnitude depended strongly on the finite well depth.
Abstract: We present variational calculations of the eigenstates in an isolated-quantum-well structure subjected to an external electric field. At weak fields a quadratic Stark shift is found whose magnitude depends strongly on the finite well depth. In addition, the electric field induces a spatial shift of the particle wave function along or opposite to the field direction, depending on the sign of the particle mass. This field-induced spatial separation of conduction and valence electrons in GaAs quantum wells decreases the overlap between their associated wave functions, leading to a reduction of interband recombination.
644 citations
TL;DR: In this article, the motion of a quantum mechanical particle is studied in the presence of a periodic potential and frictional forces, and the behavior changes from diffusion to localization depending on the parameters.
Abstract: The motion of a quantum mechanical particle is studied in the presence of a periodic potential and frictional forces. Depending on the parameters, the behavior changes from diffusion to localization.
356 citations
TL;DR: In this paper, Wigner's friends and their amnesia are described and compared with the information transfer in Quantum Measurements: Irreversibility and Amplification, and Information Transfer of Quantum Measurement: Information Transfer in Quantum Information Transfer and Non-Demolition Measurements.
Abstract: The Glorious Days of Physics.- The Glorious Days of Physics.- Foundations.- to General Relativity.- Review of the Quantum Mechanical Measurement Problem.- On State Reduction and Observation in Quantum Optics: Wigner's Friends and Their Amnesia.- Information Transfer in Quantum Measurements: Irreversibility and Amplification.- To Fathom Space and Time.- Elementary Quantum Phenomenon as Building Unit.- A Measure of the Distinguishability of Quantum States.- What is an Electron? Relativistic Electron Theory and Radiative Processes.- Methods of Quantum Optics.- to Stochastic Processes.- Fluctuations in Quantum Optical Systems.- Quantum Fluctuations in Non Linear Optics.- Quantum Communication, Quantum Measurement, TCS and QND.- Phase Conjugate Optics and Applications to Interferometry and to Laser Gyros.- Selected Topics of Laser Spectroscopy of Atoms and Molecules.- Experimental Gravitation.- Experimental Gravity, Gravitational Waves, and Quantum Nondemolition: An Introduction.- Some Remarks on the Interaction Between Precision Physical Measurement and Fundamental Physical Theories.- Proper Time Experiments in Gravitational Fields with Atomic Clocks, Aircraft, and Laser Light Pulses.- Laser Ranging to Retro-Reflectors on the Moon as a Test of Theories of Gravity.- The Meaning of the Lunar Laser Ranging Experimental Results for Gravitational Theory.- Gravitational Wave Detectors Using Laser Interferometers and Optical Cavities: Ideas, Principles and Prospects.- Gravitational Wave Detectors Using Laser Interferometers and Optical Cavities: Some Practical Aspects and Results.- The Munich Gravitational Wave Detector Using Laser Interferometry.- Quantum Nondemolition Measurements.- On the Quantum-Non-Demolition Measurement of the Energy of Optical Quanta.- Detection of External Force on an Oscillator by Measurement of Its Coordinate Integral.- Readout State Preparation and Quantum Non-Demolition.- Quantum Noise in the Interferometer Detector.- Quantum Noise and QND Measurements.- Non Back-Reacting Instrumentation for Low-Temperature Gravitational Wave Detectors.- Testing General Relativity Using Quantum Interference.- Generalized Space Time Parametric Processing Arrays and Relativistic Experiments.
247 citations
TL;DR: In this article, the Mandelstam-Tamm time-energy inequality is exploited to obtain a transparent expression of the lifetime energy uncertainty relation for decaying quantum systems along with some useful features of the quantum non-decay probability.
Abstract: The Mandelstam-Tamm time-energy inequality is exploited to obtain a transparent expression of the lifetime-energy uncertainty relation for decaying quantum systems along with some useful features of the quantum non-decay probability.
192 citations
TL;DR: In this paper, a quantum mechanical compound state of an input state and its output state generated through a communication channel is constructed, and the mutual information of quantum communication theory is defined by using the compound state, and its fundamental properties are studied.
Abstract: A quantum mechanical compound state of an input state and its output state generated through a communication channel is constructed. The mutual information of quantum communication theory is defined by using the compound state, and its fundamental properties are studied.
157 citations
TL;DR: In this paper, a quantum action variable is defined in the context of a quantum Hamilton-Jacobi theory, which can be used to find the exact bound-state energy levels without solving an equation of motion for the system wave functions.
Abstract: A quantum action variable is defined in the context of a quantum Hamilton-Jacobi theory. The action variable can be used to find the exact bound-state energy levels of a quantum system without solving an equation of motion for the system wave functions.
141 citations
137 citations
TL;DR: In this article, a quantum Kolmogorov-Arnol'd-Moser-like theorem is formulated with use of an existence condition of a unique transformation between eigenstates of integrable and nonintegrable Hamiltonians.
Abstract: A quantum Kolmogorov-Arnol'd-Moser-like theorem is formulated with use of an existence condition of a unique transformation between eigenstates of integrable and nonintegrable Hamiltonians. This condition determines the ability to assign local quantum numbers to eigenstates of nonintegrable Hamiltonians and explains localization phenomena.
TL;DR: In this article, a generating functional for real-time Green functions in quantum statistical mechanics in the context of thermofield dynamics is constructed, and the KMS condition is taken as an axiom which together with field equations fixes the generating functional.
TL;DR: In this paper, the general form of dynamics which preserve the set of closed linear submanifolds (i.e., properties) is deduced, and the result generalizes Wigner's theorem and provides a model of some irreversible phenomena like spin relaxation, damped oscillator, etc.
Abstract: General dynamics compatible with the Hilbert space structure of quantum kinematics are considered. The general form of dynamics which preserve the set of closed linear submanifolds (i.e., properties) is deduced. Since the orthogonality relation is not necessarily preserved, the result generalizes Wigner’s theorem and provides a model of some irreversible phenomena like spin relaxation, damped oscillator, etc. Connections with quantum logic and with statistical mechanics are presented.
TL;DR: In this paper, a way to construct an extension of the classical compound state in quantum systems has been presented, which is called the quantum compound state (QCS) and is defined as follows:
Abstract: When a state of a physical system dynamically changes to another state, it is important to know the correlation existing between the initial state and the final state. This correlation is described by a compound state (measure) in classical systems. In this note, we show a way how to construct such a compound state in quantum systems which is an extension of the classical compound state.
TL;DR: In this article, it was shown that for the quantum open systems, it is possible to construct probability distributions for the values at all times of certaion observables, without the continual measurement of such observables perturbing the dynamics of the system.
Abstract: Starting from the recently introduced formalism of continual measurements in quantum mechanics, it is shown that, for the quantum open systems, it is possible to construct probability distributions for the values at all times of certaion observables, without the continual measurement of such observables perturbing the dynamics of the system. More precisely, starting from the quantum description of an open system, a generalized stochastic process for certain observables is constructed, which is independent of the fact that these observables are actually measured or not. The example of the quantum Brownian motion is developed in detail. In such an example it is shown how thea priori arbitrary elements of the formalism are in reality determined by the dynamics of the system.
TL;DR: In this article, a reformulation and a generalization of a quantum theory of non-conservative (dissipative) systems was presented, which can be equivalently described by the Schrodinger or Heisenberg picture.
Abstract: We present here in a systematic way a reformulation and a generalization of a quantum theory of nonconservative (dissipative and antidissipative) systems already outlined by us many years ago. In particular, following a procedure first introduced by Levi Civita we give a detailed formulation of the corresponding classical Lagrangian and Hamiltonian treatments and consequently we show that quantum nonconservative systems can be equivalently described by the Schrodinger or Heisenberg picture. Furthermore, a detailed discussion of uncertainty rules for nonconservative systems is developed. By means of such a formulation it is possible to overcome easily criticisms raised against the so-called Caldirola-Kanai equation. Finally the connection between the Schrodinger equation for nonservative systems and the master equation is shortly discussed and some new possible developments of the theory are suggested.
TL;DR: In this paper, the authors study a problem in group representation theory motivated by relativistic quantum field theory, where the fundamental solution of the Schrodinger equation, analytically continued to imaginary time, is given by the well-known Feynman-Kac formula.
Abstract: In this paper we study a problem in group representation theory motivated by relativistic quantum field theory. One of the most powerful approaches to constructing models of relativistic quantum fields relies on Euclidean field theory, a description of quantum field theory in which time is purely imaginary. The basic objects of Euclidean field theory (the Euclidean Green's- or Schwinger functions) can often be expressed in terms of functional integrals. The construction of quantum field models is thereby "reduced to quadratures". A well-known, simple example of this method is the reformulation of quantum mechanisms by means of Wiener integrals. (The fundamental solution of the Schrodinger equation, analytically continued to imaginary time, is given by the well-known Feynman-Kac formula; see e.g. [15], [19].) In this approach one faces the problem of analytic continuation back to real time. While this problem is elementary in non-relativistic quantum mechanics, it is rather intricate in relativistic quantum field theory. For some class of relativistic quantum field theories, a fairly general solution to this problem was given in papers by Osterwalder and
01 Jan 1983
TL;DR: The conceptual problems generated by the generally accepted interpretation of quantum mechanics overshadow in philosophical depth those generated by older quantum theory to such an extent that one is likely to forget the latter as mentioned in this paper.
Abstract: The conceptual problems generated by the generally accepted interpretation of quantum mechanics overshadow in philosophical depth those generated by the older quantum theory (see for example the collections of basic papers edited by ter Haar, 1967, and Kangro, 1972) to such an extent that one is likely to forget the latter. Nevertheless, these were very real also, though more concrete and lying more within physics proper than those generated by quantum mechanics.
TL;DR: In this article, a nonperturbative investigation of the global behavior of quantum systems with time-periodic Hamiltonians is presented, and it is shown that such systems, if bounded and nonresonant, will reassemble themselves infinitely often in the course of time.
Abstract: Results of a nonperturbative investigation of the global behavior of quantum systems with time-periodic Hamiltonians are presented. These include the proof of a theorem stating that such systems, if bounded and nonresonant, will reassemble themselves infinitely often in the course of time. In order to illustrate the applicability of this result, an analytic study of a driven harmonic oscillator is presented, together with computer simulations of quantum maps describing the dynamics of a pulsed electron in a well and a periodically kicked rotor. A quantitative study of resonance excitation also shows that in practical situations recurrence is pervasive. Several unique quantum effects are analyzed, and their relevance to the classical limit is discussed. A formula is derived for recurrence times, and computer experiments are performed to test its validity.
TL;DR: In this paper, a review of the quantum statistical electrodynamics of resonant atoms is presented, with a special emphasis given by phenomena associated with aggregates of like atoms in which resonant interactions are possible.
TL;DR: In this paper, the authors discuss the role of quantum mechanics as a superb calculational tool for quantum mechanics and their application in quantum optics and quantum electronics, such as quantum optics, which owe their very existence to quantum mechanics.
Abstract: Conventional quantum mechanics is a superb calculational tool. It has successfully solved mysteries ranging from macroscopic superconductivity1(a) to the microscopic theory of the electron1(b) and has provided deeper insight into the nature of the vacuum1(c) on the one hand and the description of the nucleon1(d) on the other. Whole new fields2(a)−2(b) such as quantum optics and quantum electronics owe their very existence to this body of knowledge.
TL;DR: Two recent precision experiments provide conclusive evidence against any local hidden variables theory and in favor of standard quantum mechanics.
Abstract: Two recent precision experiments provide conclusive evidence against any local hidden variables theory and in favor of standard quantum mechanics. Therefore the epistemology and the ontology of quantum mechanics must now be taken more seriously than ever before. The consequences of the standard interpretation of quantum mechanics are summarized in nontechnical language. The implications of the finiteness of Planck's constant (h > 0) for the quantum world are as strange as the implications of the finiteness of the speed of light (c < infinity for space and time in relativity theory. Both lead to realities beyond our common experience that cannot be rejected.
TL;DR: In this paper, it was shown that the radiative decay of an excited atom can be viewed equivalently as the result of the vacuum fluctuations of the electromagnetic field or as the resulting radiative self-force of the electron.
Abstract: The understanding that has been gained of accelerated vacua sheds new light on the classic issue of the self-force suffered by a uniformly accelerated charge. Moreover, the fact that, as a result of quantum theory, the radiative decay of an excited atom can be viewed equivalently as the result of the vacuum fluctuations of the electromagnetic field or as the result of the radiative self-force of the electron is shown to be nontrivially linked with the equivalence principle.
TL;DR: In this paper, the authors report the progress of the path integral approach to quantum cosmology and show how the quantization of the conformal degree of freedom leads to stationary states for the quantum analogues of the classical models.
TL;DR: In this paper, the authors investigate the effect of information transfer in quantum systems on the phase coherence between the states of the privileged basis in the system Hilbert space and argue that states of this pointer basis correspond to the classical states of observables of the quantum system in question.
Abstract: The aim of these lectures is to investigate the transfer of information occurring in course of quantum interactions. In particular, I shall explore circumstances in which such an information transfer with the quantum environment of the considered quantum system leads to the destruction of the phase coherence between the states of the privileged basis in the system Hilbert space. This basis shall be called the pointer basis. I shall argue that states of this pointer basis correspond to the “classical” states of the observables of the quantum system in question.