Entanglement Enabled Intensity Interferometry

Abstract

Intensity interferometry (Hanbury Brown -Twiss effect) is an interesting and useful concept that is usually presented as a manifestation of the quantum statistics of indistinguishable particles. Here, by exploiting possibilities for projection and entanglement, we substantially widen the scope of its central idea, removing the requirement of indistinguishability. We thereby potentially gain access to a host of new observables, including subtle polarization correlations and entanglement itself. Our considerations also shed light on the physical significance of superselection.

Quantum Hall realization of polarized intensity interferometry

“…This observation led to the birth of intensity interferometry. Since then intensity interferometry has been explored in a variety of fields ranging from nuclear to condensed matter physics and new perspectives are still being explored [2,3]. Quantum mechanically, intensity interferometry refers to a phenomenon wherein a quantum state describing a pair of particles (emanating from two independent sources) interfere with itself.…”

“…1(a). The figure represents a minimal scenario for a two source (S (1,2) ) -two detector (D (1,2) ) set-up where an electron shot from a given source has a finite probability of reaching either of the two detectors which is an essential requirement for realizing HB-T interferometry. Our set-up comprises of a Hall bar geometry hosting a ν = 2 state with a single gate in the middle which is tuned such that the inner edge of the ν = 2 state is fully reflecting while the outer edge is fully transmitting.…”

“…Later we have shown that the interactions in the mixer regions do not modify our results in experimentally feasible window of parameter space. The four continuous edges (two spin up and two spin down) which connect S (1,2) to D (1,2) are described by the model Hamiltonian [18] given by…”

“…Now we will proceed to show that this in-plane rotation of the magnetic field, viz. tuning φ with Γ kept constant, in any one of the mixers leads to oscillations only in the cross-correlated noise measured between two drains (D (1) and D (2) ) while the current and the auto-correlated noise measured at each drain remain insensitive to it. These oscillations are manifestations of two-particle interference pattern [19][20][21].…”

“…Cross-correlated noise:-The proposed set-up in Fig. 1(a) shows two sources S (1) and S (2) that are held at a bias V with respect to the detectors D (1) and D (2) (both being virtually grounded) between which the cross-correlated noise is measured [22]. Following Ref.…”