Optical photons detected without being destroyed

Andreas Reiserer

Lloyd M. Davis

Streak-camera detection of moving interference fringes with single-photon resolution constitutes a novel Young's experiment in which the exact frequency of each detected photon cannot be specified without destroying the visibility of the interference pattern. The experiment demonstrates first-order cross spectral coherence between resolvable frequencies, in which case the optical frequency of the detected light must be calculated in terms of a time-dependent spectrum.

Gilles Nogues, Arno Rauschenbeutel, S. Osnaghi +3 more

Marvellous Onuma-Kalu

I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. ii The act of measuring an observable of a quantum system introduces backaction noise to the measured system. In the most extreme case, the system gets destroyed with its state left unavailable for future measurement. An example is the photodetection process where photons are destroyed upon detection. It is desirable to consider schemes that avoid the back action effect induced on detected observable due to the measurement. Such measurement scheme in which one is able to repeat a measurement on a physical observable, with the result of each measurement being the same for all measurement times is known as quantum non-demolition (QND) measurement. With the QND measurement idea, it has become possible to detect photons without destroying its state. In this thesis, we present an optical QND measurement scheme known as the Mode invisibility technique to measure

Keyu Xia, Mattias Johnsson, P. L. Knight +1 more

Detecting a single photon without absorbing it is a long-standing challenge in quantum optics. All experiments demonstrating the nondestructive detection of a photon make use of a high quality cavity. We present a cavity-free scheme for nondestructive single-photon detection. By pumping a nonlinear medium we implement an interfield Rabi oscillation which leads to a ∼π phase shift on a weak probe coherent laser field in the presence of a single signal photon without destroying the signal photon. Our cavity-free scheme operates with a fast intrinsic time scale in comparison with similar cavity-based schemes. We implement a full real-space multimode numerical analysis of the interacting photonic modes and confirm the validity of our nondestructive scheme in the multimode case.