Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userOperationalistic Orthogonality Condition for Single-Mode Biphotons (Qutrits)
72
0
0.0
(
0
)
Added by
Gleb A. Maslennikov
Publication date
2003
fields
Physics
and research's language is
English
Ask ChatGPT about the research
No Arabic abstract
An arbitrary polarization state of a single-mode biphoton is considered. The operationalistic criterion is formulated for the orthogonality og these states. It can be used to separate a biphoton with an arbitrary degree of polarization from a set of biphotons orthogonal to it. This is necessary fro the implementation of quantum cryptography protocol based on three-level systems. The experimental test of this criterion amounts to the observation of the anticorrelation effect for a biphoton with an arbitraty polarization state.
rate research
Read More
We demonastrate experimental technique for generating spatially single-mode broadband biphoton field. The method is based on dispersive optical element which precisely tailors the structure of type-I SPDC frequency angular spectrum in order to shift different spectral components to a single angular mode. Spatial mode filtering is realized by coupling biphotons into a single-mode optical fiber.
We theoretically investigate light scattering from an array of atoms into the guided modes of a waveguide. We show that the scattering of a plane wave laser field into the waveguide modes is dramatically enhanced for angles that deviate from the geometric Bragg angle. We derive a modified Bragg condition, and show that it arises from the dispersive interactions between the guided light and the atoms. Moreover, we identify various parameter regimes in which the scattering rate features a qualitatively different dependence on the atom number, such as linear, quadratic, oscillatory or constant behavior. We show that our findings are robust against voids in the atomic array, facilitating their experimental observation and potential applications. Our work sheds new light on collective light scattering and the interplay between geometry and interaction effects, with implications reaching beyond the optical domain.
A general protocol in Quantum Information and Communication relies in the ability of producing, transmitting and reconstructing, in general, qunits. In this letter we show for the first time the experimental implementation of these three basic steps on a pure state in a three dimensional space, by means of the orbital angular momentum of the photons. The reconstruction of the qutrit is performed with tomographic techniques and a Maximum-Likelihood estimation method. In this way we also demonstrate that we can perform any transformation in the three dimensional space.
Quantum information carriers with higher dimension than the canonical qubit offer significant advantages. However, manipulating such systems is extremely difficult. We show how measurement induced non-linearities can be employed to dramatically extend the range of possible transforms on biphotonic qutrits; the three level quantum systems formed by the polarisation of two photons in the same spatio-temporal mode. We fully characterise the biphoton-photon entanglement that underpins our technique, thereby realising the first instance of qubit-qutrit entanglement. We discuss an extension of our technique to generate qutrit-qutrit entanglement and to manipulate any bosonic encoding of quantum information.
We proposed the procedure of measuring the unknown state of the three-level system - the qutrit, which was realized as the arbitrary polarization state of the single-mode biphoton field. This procedure is accomplished for the set of the pure states of qutrits; this set is defined by the properties of SU(2) transformations, that are done by the polarization transformers.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
