Quantum Entanglement | 22 May 2020
Why in News
Recently, the scientists from S.N. Bose National Centre for Basic Sciences (SNBNCBS), Kolkata have developed a novel protocol to find out whether a pair of electrons is in an entangled state.
- This novel protocol to measure the status of entanglement is known as Device Independent Self Testing (DIST) method.
Key Points
- Device Independent Self Testing (DIST) Method:
- This method can be used to overcome safety concerns in quantum entanglement as it enables the verification of entanglement in an unknown quantum state of two photons without having direct access to the state, or complete trust in the measurement devices.
- In several practical situations, one of the parties may be fully trusted, whereas, the other may not be trusted like in the case of server-client relationship in banking transactions.
- Quantum Entanglement:
- It is the physical phenomenon that occurs when a pair or group of particles is generated and they interact in such a way that the quantum state of each particle of the pair or group cannot be described independently of the state of the others.
- In this quantum mechanical phenomenon, the quantum states of two or more objects have to be described with reference to each other, even though the individual objects may be spatially separated.
- This leads to correlations between observable physical properties of the systems.
- Albert Einstein dismissed this idea as a 'spooky action'.
- Importance:
- Entangled states are key resources to facilitate many quantum information processing tasks and quantum cryptographic protocols.
- The entangled pairs of electrons can be safely used as resources for facilitating quantum information processing tasks.
- Challenges:
- Fragility: Entanglement is fragile and is easily lost during the transit of photons through the environment. Hence, it is extremely important to know whether a pair of photons is entangled, in order to use them as resources.
- Safety: Verification of entanglement requires the use of measurement devices, but such devices may be hacked and cannot be trusted fully.