Article - Free access
Other version: http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6VMT-4GGWJ06-2-83&_cdi=6159&_user=779890&_orig=search&_cover...
Ground state entanglement energetics
|Published in||Physica E: Low-dimensional Systems and Nanostructures. 2005, vol. 29, no. 1-2, p. 272-282|
|Abstract||We consider the ground state of simple quantum systems coupled to an environment. In general the system is entangled with its environment. As a consequence, even at zero temperature, the energy of the system is not sharp: a projective measurement can find the system in an excited state. We show that energy fluctuation measurements at zero temperature provide entanglement information. For two-state systems which exhibit a persistent current in the ground state, energy fluctuations and persistent current fluctuations are closely related. The harmonic oscillator serves to illustrate energy fluctuations in a system with an infinite number of states. In addition to the energy distribution we discuss the energy-energy time-correlation function in the zero-temperature limit.|
|Keywords||Quantum bit — Mesoscopic systems — Entangled states — Quantum system — Time correlation function — Harmonic oscillators — Energy levels — Persistent currents — Transport processes — Cooper pairs — Excited states — Quantum computer — Entanglement energetics — Energy fluctuations — Decoherence|
|BUTTIKER, Markus, JORDAN, Andrew N. Ground state entanglement energetics. In: Physica E: Low-dimensional Systems and Nanostructures, 2005, vol. 29, n° 1-2, p. 272-282. https://archive-ouverte.unige.ch/unige:4170|