Spatial interference between pairs of disjoint optical paths with a single chaotic source

Abstract

We demonstrate a novel second-order spatial interference effect between two indistinguishable pairs of disjoint optical paths from a single chaotic source. Beside providing a deeper understanding of the physics of multiphoton interference and coherence, the effect enables retrieving information on both the spatial structure and the relative position of two distant doublepinhole masks, in the absence of first order coherence. We also demonstrate the exploitation of the phenomenon for simulating quantum logic gates, including a controlled-NOT gate operation.

Symmetries and entanglement features of inner-mode-resolved correlations of interfering nonidentical photons

“…3b) and 3c), respectively, define the degree of entanglement for each W-state as a function of the relative detected inner-mode parameters {β d } and of the input inner-mode parameters α 1 − α 2 according to Eq. (12). Evidently, the states encoded into the outcomes of the inner-mode measurements exhibit arbitrary degrees of tripartite entanglement of the W-state type from complete separability up to maximal entanglement (Fig.…”

“…The nonclassical interference of light [1][2][3] is one of the main consequences of the quantum nature of the electromagnetic field and lies at the heart of many quantum optics experiments [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. It plays a central role in a variety of applications ranging from quantum computing [4,[15][16][17][18][19] over quantum communication and quantum cryptography [20,21] to quantum metrology and state tomography [9-12, 14, 22-24].…”

“…2 (blue lines). For example, the permutation (12)(3) together with the parity operation is represented by the negative permutation matrix −R (12)…”

An optical multimode fiber as pseudothermal light source

“…Potential applications of fiber pseudo-TLS are, e.g., the implementation of Franson interferometers [34] or the simulation of a controlled-NOT gate [35,36]. Fiber pseudo-TLS might also prove useful for tasks in quantum imaging or quantum metrology, e.g., measurements of higher order spatial intensity correlations in irregular arrangements of pseudo-TLS in 2D.…”

The physics of thermal light second-order interference beyond coherence

“…Furthermore, the same effect can be realised also in the spatial domain, by substituting the two Mach-Zehnder interferometers with two double slits and performing spatially correlated measurements at the output, as proposed in Ref. [40]. Indeed, it did not take too long until experimental demonstrations of this effect were first reported both in the temporal and spatial domain in Refs.…”