Abstract.
What are the fundamental limits of quantum correlations in linear systems? In my talk I will doscuss universal, device-independent bounds on the internal correlations of linear time-invariant (LTI) bosonic networks. By utilizing a 'quantum KYP' contractive-map approach, I will show that the stability of a system and the preservation of canonical commutation relations (CCR) impose strict constraints on performance.
In particular, the strength of any 'cross-path' interaction is fundamentally limited by a cascade of damped single poles, determined by the system's effective decay rates. These results provide lower bounds on noise and correlations that depend only on stability and linewidths, rather than specific hardware designs. We apply these limits to two-mode dissipative systems and three-mode optomechanical architectures, providing necessary 'design-level' condition for squeezing and the observation of mechanical entanglement.
(The slides will be available here)