Related papers: Two-sequential Conclusive Discrimination between B…
Entanglement swapping and heralding are at the heart of many protocols for distributed quantum information. For photons, this typically involves Bell state measurements based on two-photon interference effects. In this context, hybrid…
Coherent signal containing squeezed noise in a mixed state of radiation field is considered here as a non-Gaussian mixture of a coherent state density operator and a squeezed state density operator, as opposed to the usual well known…
In this article, we revisit the century-old question of the minimal set of observables needed to identify a quantum state: here, we replace the natural coincidences in their spectra by effective ones, induced by an imperfect measurement. We…
In the present paper I formulate a framework that accommodates many unambiguous discrimination problems. I show that the prior information about any type of constituent (state, channel, or observable) allows us to reformulate the…
Weak cross-Kerr nonlinearities between single photons and coherent states are the basis for many applications in quantum information processing. These nonlinearities have so far mainly been discussed in terms of highly idealized single-mode…
Due to quantum noise fluctuations, the rate of error achievable in decision problems involving several possible configurations of a scattering system is subject to a fundamental limit known as the Helstrom bound. Here, we present a general…
We use a fiber based double slit Young interferometer for studying the far-field spatial distribution of the two-photon coincidence rate (coincidence pattern) for various quantum states with different degree of spatial entanglement. The…
Phase super-sensitivity is obtained when the sensitivity in a phase measurement goes beyond the quantum shot noise limit, whereas super-resolution is obtained when the interference fringes in an interferometer are narrower than half the…
We investigate the unambiguous comparison of quantum states in a scenario that is more general than the one that was originally suggested by Barnett et al. First, we find the optimal solution for the comparison of two states taken from a…
Universal photon blockade in a two-mode Jaynes-Cummings model incorporating third-order Kerr nonlinearity is demonstrated with a single two-level atom coupled to a waveguide microcavity. Realization of this universal photon blockade is…
Optical quantum information processing critically relies on Bell-state measurement, a ubiquitous operation for quantum communication and computing. Its practical realization involves the interference of optical modes and the detection of a…
We employ quantum state discrimination theory to establish the ultimate limit for spoofing detection in electromagnetic signals encoded with random quantum states. Our analysis yields an analytical expression for the optimal bound, which we…
We present a new method to observe direct experimental evidence of Jaynes--Cummings nonlinearities in a strongly dissipative cavity quantum electrodynamics system, where large losses compete with the strong light-matter interaction. This is…
Measurement-based heralded entanglement schemes have served as the primary link between physically separated qubits in most quantum information platforms. However, the impossibility of performing a deterministic Bell measurement with linear…
Polarized light microscopy using path-entangled $N$-photon states (i.e., the N00N states) has been demonstrated to surpass the shot-noise limit at very low light illumination. However, the microscopy images suffer from divergence of phase…
Several proposed techniques for distinguishing between optical coherent states are analyzed under a physically realistic model of photodetection. Quantum error probabilities are derived for the Kennedy receiver, the Dolinar receiver and the…
The ability to entangle distant quantum nodes is essential for the construction of quantum networks and for quantum information processing. For solid-state quantum emitters used as qubits, it can be achieved by photon interference. When the…
We investigate the implementation of binary projective measurements with linear optics. This problem can be viewed as a single-shot discrimination of two orthogonal pure quantum states. We show that any two orthogonal states can be…
Discussions about quantum interference, indistinguishability and superpostion between quantum states goes back to the beginning of quantum mechanics, but the theoretical problem concerning quantitative measures for quantum coherence was…
We demonstrate and characterize interference between discrete photons emitted by two separate semiconductor quantum dot states in different samples excited by a pulsed laser. Their energies are tuned into resonance using strain. The photons…