Quantum photonic interconnect and entanglement distribution between two integrated Si photonic chips. Credit: arXiv:1508.03214 [quant-ph] Explore further For modern electronic devices to work, there must be some channels for the different parts to use to convey information between them—such channels are usually either wire carrying electricity or fiber carrying photons and are called interconnects. But as researchers shrink down the parts, the interconnects more and more represent a bottleneck. Worse, as scientists conduct research into creating a truly quantum computer, the problem of creating interconnects for them has become a serious issue. Now, in this new effort, the research team is claiming to have found a solution—one where a separate entanglement stage is used to preserve the original entanglement needed as part of normal operations—demonstrating a way to connect two photonic chips.To allow for interconnection, the researchers ran two sources of photons along one of the chips, on channels that overlapped—when the photons met in the overlap area, they became entangled and that entanglement was then carried along different paths in the chip. They next ran the photons through a device that converted that path entanglement into a whole new type of entanglement, one that involved polarization, which also caused the creation of new entangled photons. Those newly entangled polarized photons were then passed into an optical fiber that ran between the two chips. The whole process was then reversed in the second chip, where the polarized photons were converted back to path entangled photons, which then behaved exactly like the photons in the first chip. The team conducted multiple different types of tests to prove that entanglement was preserved throughout the interconnection process.The team acknowledges that the process is still too inefficient to be implemented into real devices, but believe further refinement will lead to a usable solution. But, they have shown that it is possible to interconnect quantum devices, which should come as a relief to those working on building a quantum computer. © 2015 Phys.org Journal information: arXiv New method of quantum entanglement vastly increases how much information can be carried in a photon This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. More information: Quantum Photonic Interconnect, arXiv:1508.03214 [quant-ph] arxiv.org/abs/1508.03214AbstractIntegrated photonics has enabled much progress towards quantum technologies. However, many applications, e.g. quantum communication, sensing, and distributed and cloud quantum computing, require coherent photonic interconnection between separate sub-systems, with high-fidelity distribution and manipulation of entanglement between multiple devices being one of the most stringent requirements of the interconnected system. Coherently interconnecting separate chips is challenging due to the fragility of these quantum states and the demanding challenges of transmitting photons in at least two media within a single coherent system. Here, we report a quantum photonic interconnect demonstrating high-fidelity entanglement distribution and manipulation between two separate chips, implemented using state-of-the-art silicon photonics. Entangled states are generated and manipulated on-chip, and distributed between the chips by interconverting between path-encoding and polarisation-encoding. We use integrated state analysers to confirm a Bell-type violation of S=2.638+-0.039 between two chips. With improvements in loss, this quantum interconnect will provide new levels of flexible systems and architectures for quantum technologies.via Arxiv Blog (Phys.org)—An international team of researchers has found a way to interconnect two quantum devices, allowing photons to move between the two, all while preserving entanglement. In their paper they have uploaded to the preprint server arXiv, the team describes their process and their hopes for tweaking it to make it more efficient. Citation: A way has been found to interconnect quantum devices including preserving entanglement (2015, August 21) retrieved 18 August 2019 from https://phys.org/news/2015-08-interconnect-quantum-devices-entanglement.html
Kolkata: Following the direction of Chief Minister Mamata Banerjee, the state Transport department is going to start a state-wide drive to check the fitness of public transport vehicles.According to a senior official of the state Transport department, checking of goods vehicles is carried out round-the-year.”Now, we are going to initiate a process to carry out periodical fitness checking of public transport vehicles,” the official said, adding that initially emphasis will be given on checking fitness of buses and mini-buses that ply on different routes. It has been stated that there are two reasons behind starting fitness check of public transport vehicles. First of all, it will help in reducing the number of road accidents and will also ensure that commuters get better service, particularly as the bus fares have recently gone up. It may be mentioned that the Chief Minister has called for necessary steps to ensure periodical fitness checking of vehicles to avoid accidents. Also Read – Rain batters Kolkata, cripples normal lifeSince stress will be initially given on checking the fitness of buses, the official said that they will be checking whether a passenger is facing any problem while travelling in the vehicles. Citing some examples, the official added that they will be checking the condition of tyres being used in the public transport vehicles.It may be mentioned that use of good quality tyres in buses is mandatory to check accidents. According to experts, the chances of skidding goes up when sudden brake is applied if the condition of tyre is poor or if the vehicle is fitted with rethreaded tyres. Mainly in monsoon, many accidents take place due to the use of rethreaded tyres, as vehicles do not stop despite applying brakes. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedBesides checking the quality of tyres, the officials will also check the overall condition of a bus to find out whether water drips from its ceiling and causes inconvenience to passengers. They will also check the condition of seats.”The checking will be carried out at different points and it will be done following the pick and choose method. Necessary steps will be taken if they find that the vehicles are not maintained properly,” the official said, adding that their endeavour is to ensure better amenities for passengers.The bus owners, in whose vehicles any fault is found, will be directed to repair the same, before plying them again.This comes at the time when the state government has taken up the state-wide Safe Drive Save Life campaign to bring down the rate of accidents.
In what comes as a rare tributary endeavor of Khadi and Village Industries Commission (KVIC) to Rashtrapita on his 150th Birth Anniversary Year, Vice President Muppavarapu Venkaiah Naidu will unveil Mahatma Gandhi’s ‘Grand Wall Mural’ at New Delhi Municipal Corporation (NDMC) Main Building on January 31, 2019.This 150 square meters clay mural is made of ‘Kulhads’ from the hands of 150 village potters across India, who assembled to make it at Morbi in Gujarat. Also Read – Add new books to your shelfEnthused with the classical efforts shown by the artisans, KVIC Chairman Vinai Kumar Saxena said that KVIC had decided to mark the occasion with practical display of Gandhian thoughts on village industries, at a time when the whole nation is celebrating Gandhiji’s 150th birth anniversary in different styles. “With the co-operation of these 150 highly-skilled potters from all over the country, we have made this wall mural, using their kulhads,” he said, adding, “They had brought clay of their respective regions which has been mixed to produce the kulhads for the mural. Kulhads of 75 mm diameter and 90 mm height were made on electric pottery wheels given by KVIC.” “The potters have finished the kulhads as per tradition and design requirements. Altogether 5,000 kulhads were produced, of which the best 3,870 kulhads – making them all-weather proof by baking at high temperatures and glazing – were used in the final design.” Ahmedabad-based designer terracotta and ceramic art studio, Clay Club Innovations, had designed the artwork. Expressing his happiness on this tributary endeavour of KVIC, the Minister of State for MSME Giriraj Singh, who will be the Guest of Honour on this occasion, said, “It will really be a proud moment for the nation when KVIC’s grand mural will prominently be displayed in the heart of the national Capital – showcasing the combined ‘sweaty’ efforts of village potters across the nation.”