Can Intense Quantum Light Beat Classical Uncertainty Relations?

TL;DR

This paper derives a general lower bound on the joint time-delay and frequency-bandwidth uncertainties for multimode quantum light, revealing how nonclassical states can surpass classical limits due to entanglement properties.

Contribution

It introduces a universal lower bound for quantum uncertainties in multimode light, linking nonclassical corrections to photon number and entanglement monogamy.

Findings

Nonclassical correction scales inversely with photon number

Derived a general lower bound for joint uncertainties

Highlights the role of entanglement in quantum advantage

Abstract

Uncertainty relations are fundamental to quantum mechanics, encoding limits on the simultaneous measurement of conjugate observables. Violations of joint uncertainty bounds can certify entanglement -- a resource critical for quantum information protocols and increasingly relevant in strong-field physics. Here, we investigate the pairwise time-delay and frequency-bandwidth uncertainties for arbitrary multimode quantum states of light, deriving a general lower bound for their joint product. We find that the nonclassical correction scales inversely with the average photon number, a behavior rooted in the so-called ``monogamy of entanglement''. These results clarify the intensity scaling of quantum advantages in nonclassical light states and highlight the interplay between entanglement and photon statistics.