Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Bell inequalities: CHSH version

Description

This lecture covers the generation of polarization-entangled photons using SPD, the production and selection of the entangled state, the concept of Bell inequalities with the CHSH version, and other implementations with two SPDC sources. It also delves into the SPDC Hamiltonian, the biphoton wavefunction, and the phase memory in two-photon down conversion.

Official source

Related concepts (16)

Quantum entanglement

Quantum entanglement is the phenomenon that occurs when a group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics not present in classical mechanics.

Bell test

A Bell test, also known as Bell inequality test or Bell experiment, is a real-world physics experiment designed to test the theory of quantum mechanics in relation to Albert Einstein's concept of local realism. Named for John Stewart Bell, the experiments test whether or not the real world satisfies local realism, which requires the presence of some additional local variables (called "hidden" because they are not a feature of quantum theory) to explain the behavior of particles like photons and electrons.

Bell's theorem

Bell's theorem is a term encompassing a number of closely related results in physics, all of which determine that quantum mechanics is incompatible with local hidden-variable theories, given some basic assumptions about the nature of measurement. "Local" here refers to the principle of locality, the idea that a particle can only be influenced by its immediate surroundings, and that interactions mediated by physical fields cannot propagate faster than the speed of light.

Quantum teleportation

Quantum teleportation is a technique for transferring quantum information from a sender at one location to a receiver some distance away. While teleportation is commonly portrayed in science fiction as a means to transfer physical objects from one location to the next, quantum teleportation only transfers quantum information. The sender does not have to know the particular quantum state being transferred. Moreover, the location of the recipient can be unknown, but to complete the quantum teleportation, classical information needs to be sent from sender to receiver.

Nonlinear optics

Nonlinear optics (NLO) is the branch of optics that describes the behaviour of light in nonlinear media, that is, media in which the polarization density P responds non-linearly to the electric field E of the light. The non-linearity is typically observed only at very high light intensities (when the electric field of the light is >108 V/m and thus comparable to the atomic electric field of ~1011 V/m) such as those provided by lasers. Above the Schwinger limit, the vacuum itself is expected to become nonlinear.

Related lectures (31)

Quantum Entanglement

Explores quantum entanglement, Bell inequalities, and self-testing in quantum systems.

Quantum Entanglement: From Einstein to Bell

Delves into the journey from Einstein and Bell's debates to the practical applications of quantum entanglement, including quantum teleportation and key distribution.

Bell Test: Distinguishing Physical Theories

Introduces the Bell test, exploring conclusions from local causality and quantum theory.

Entanglement: Bell States

Covers the notion of entanglement, dense coding, teleportation, and Bell inequality.

Double Slit Experiment and Quantum Information Processing