Physics – Quantum Physics
Scientific paper
2008-09-11
Physics
Quantum Physics
4 pages, 2 figures
Scientific paper
As a pure quantum state is being approached via linear feedback, and the occupation number approaches and eventually goes below unity, optimal control becomes crucial. We obtain theoretically the optimal feedback controller that minimizes the uncertainty for a general linear measurement process, and show that even in the absence of classical noise, a pure quantum state is not always achievable via feedback. For Markovian measurements, the deviation from minimum Heisenberg Uncertainty is found to be closely related to the extent to which the device beats the free-mass Standard Quantum Limit for force measurement. We then specialize to optical Markovian measurements, and demonstrate that a slight modification to the usual input-output scheme -- either injecting frequency independent squeezed vacuum or making a homodyne detection at a non-phase quadrature -- allows controlled states of kilogram-scale mirrors in future LIGO interferometers to reach occupation numbers significantly below unity.
Chen Yanbei
Corbitt Thomas
Danilishin Stefan
Danzmann Karsten
Mavalvala Nergis
No associations
LandOfFree
Creation of a quantum oscillator by classical control does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Creation of a quantum oscillator by classical control, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Creation of a quantum oscillator by classical control will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-474241