# Pointer states via Decoherence in a Quantum Measurement

@article{Venugopalan1999PointerSV, title={Pointer states via Decoherence in a Quantum Measurement}, author={Anu Venugopalan}, journal={Physical Review A}, year={1999}, volume={61}, pages={012102} }

We consider the interaction of a quantum system (spin-1/2) with a macroscopic quantum apparatus (harmonic oscillator) which in turn is coupled to a bath of harmonic oscillators. Exact solutions of the Markovian Master equation show that the reduced density matrix of the system-apparatus combine decoheres to a statistical mixture where up and down spins eventually correlate with pointer states of the apparatus (harmonic oscillator), with associated probabilities in accordance with quantum…

#### 22 Citations

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